SwePub
Sök i SwePub databas

  Extended search

Träfflista för sökning "WFRF:(Halvarsson A) "

Search: WFRF:(Halvarsson A)

  • Result 1-42 of 42
Sort/group result
   
EnumerationReferenceCoverFind
1.
  • Went, M, et al. (author)
  • Author Correction: Identification of multiple risk loci and regulatory mechanisms influencing susceptibility to multiple myeloma
  • 2019
  • In: Nature communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 10:1, s. 213-
  • Journal article (peer-reviewed)abstract
    • The original version of this Article contained an error in the spelling of a member of the PRACTICAL Consortium, Manuela Gago-Dominguez, which was incorrectly given as Manuela Gago Dominguez. This has now been corrected in both the PDF and HTML versions of the Article. Furthermore, in the original HTML version of this Article, the order of authors within the author list was incorrect. The PRACTICAL consortium was incorrectly listed after Richard S. Houlston and should have been listed after Nora Pashayan. This error has been corrected in the HTML version of the Article; the PDF version was correct at the time of publication.
  •  
2.
  • Went, M, et al. (author)
  • Identification of multiple risk loci and regulatory mechanisms influencing susceptibility to multiple myeloma
  • 2018
  • In: Nature communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 9:1, s. 3707-
  • Journal article (peer-reviewed)abstract
    • Genome-wide association studies (GWAS) have transformed our understanding of susceptibility to multiple myeloma (MM), but much of the heritability remains unexplained. We report a new GWAS, a meta-analysis with previous GWAS and a replication series, totalling 9974 MM cases and 247,556 controls of European ancestry. Collectively, these data provide evidence for six new MM risk loci, bringing the total number to 23. Integration of information from gene expression, epigenetic profiling and in situ Hi-C data for the 23 risk loci implicate disruption of developmental transcriptional regulators as a basis of MM susceptibility, compatible with altered B-cell differentiation as a key mechanism. Dysregulation of autophagy/apoptosis and cell cycle signalling feature as recurrently perturbed pathways. Our findings provide further insight into the biological basis of MM.
  •  
3.
  •  
4.
  • Halvarsson, A, et al. (author)
  • Effects of new, individually adjusted, progressive balance group training for elderly people with fear of falling and tend to fall: a randomized controlled trial
  • 2011
  • In: Clinical rehabilitation. - : SAGE Publications. - 1477-0873 .- 0269-2155. ; 25:11, s. 1021-1031
  • Journal article (peer-reviewed)abstract
    • Objective: To evaluate the effects of a new, individually adjusted, progressive and specific balance group training programme on fear of falling, step execution, and gait in healthy elderly people with fear of falling and tend to fall. Design: Randomized controlled trial. Setting: The study was conducted in Stockholm County, Sweden. Subjects: Fifty-nine community dwelling elderly people were recruited by advertisement, and allocated at random to an intervention group ( n = 38) or a control group ( n = 21). Intervention: Individually adjusted, progressive and specific balance group training was given three times a week for three months. The training incorporated elements included in, and required for, independent activities of daily living, and for reactions to loss of balance during dual or multiple tasks. Main measures: Fear of falling was assessed with Falls Efficacy Scale International (FES-I). The reaction time of step execution was measured with the step-execution test, and gait was measured with GAITRite®. Results: After three months the intervention group showed significant positive changes in the FES-I ( P = 0.008), in the step-execution phase of dual-task performance ( P = 0.012), and in gait at preferred speed during single-task performance; in cadence ( P = 0.030) and, at fast speed, in velocity ( P = 0.004) and cadence ( P = 0.001). Significant decreases were also found for the likelihood of depression after participating in the training programme. Conclusion: This new balance training programme is feasible and leads to decreased fear of falling, decreased time for step execution during dual-task performance and increased velocity during fast walking.
  •  
5.
  •  
6.
  •  
7.
  •  
8.
  •  
9.
  • Halvarsson, A, et al. (author)
  • Balance training with multi-task exercises improves fall-related self-efficacy, gait, balance performance and physical function in older adults with osteoporosis: a randomized controlled trial
  • 2015
  • In: Clinical rehabilitation. - : SAGE Publications. - 1477-0873 .- 0269-2155. ; 29:4, s. 365-375
  • Journal article (peer-reviewed)abstract
    • To evaluate the effects of a balance training program including dual- and multi-task exercises on fall-related self-efficacy, fear of falling, gait and balance performance, and physical function in older adults with osteoporosis with an increased risk of falling and to evaluate whether additional physical activity would further improve the effects. Design: Randomized controlled trial, including three groups: two intervention groups (Training, or Training+Physical activity) and one Control group, with a 12-week follow-up. Setting: Stockholm County, Sweden. Participants: Ninety-six older adults, aged 66-87, with verified osteoporosis. Interventions: A specific and progressive balance training program including dual- and multi-task three times/week for 12 weeks, and physical activity for 30 minutes, three times/week. Main measures: Fall-related self-efficacy (Falls Efficacy Scale-International), fear of falling (single-item question – ‘In general, are you afraid of falling?’), gait speed with and without a cognitive dual-task at preferred pace and fast walking (GAITRite®), balance performance tests (one-leg stance, and modified figure of eight), and physical function (Late-Life Function and Disability Instrument). Results: Both intervention groups significantly improved their fall-related self-efficacy as compared to the controls ( p ≤ 0.034, 4 points) and improved their balance performance. Significant differences over time and between groups in favour of the intervention groups were found for walking speed with a dual-task ( p=0.003), at fast walking speed ( p=0.008), and for advanced lower extremity physical function ( p=0.034). Conclusions: This balance training program, including dual- and multi-task, improves fall-related self-efficacy, gait speed, balance performance, and physical function in older adults with osteoporosis.
  •  
10.
  •  
11.
  • Halvarsson, A, et al. (author)
  • Long-term effects of a progressive and specific balance-training programme with multi-task exercises for older adults with osteoporosis: a randomized controlled study
  • 2016
  • In: Clinical rehabilitation. - : SAGE Publications. - 1477-0873 .- 0269-2155. ; 30:11, s. 1049-1059
  • Journal article (peer-reviewed)abstract
    • To evaluate long-term effects of balance-training on concerns about falling, gait, balance performance, and physical function in older adults with osteoporosis and increased risk of falling. Design: Randomized controlled trial, including three groups (training, training+physical activity, and control group), with follow-ups at three, nine, and 15 months. Short-term, three-month follow-up, benefits for those who fulfilled the first follow-up ( n = 69) have previously been reported. Setting: Stockholm, Sweden. Participants: A total of 96 elderly, age 66–87, with verified osteoporosis. Interventions: Balance-training programme including dual- and multitasks, with or without supplementary physical activity, three times/week over 12 weeks. Measurements: Concerns about falling Falls Efficacy Scale -International (FES-I), walking at preferred speed with and without a cognitive dual-task and at fast speed, balance tests (one-leg stance and modified figure-of-eight), and physical function Late-Life Function and Disability Instrument (LLFDI). Results: Participants in the training group maintained positive effects throughout the study period for concerns about falling (baseline vs. 15 months, median 27.5 vs. 23 points, p < 0.001) and walking performance (baseline vs. 15 months, p ⩽ 0.05 with an improvement of 0.9–1.4 m/s). The Training+physical activity group declined to baseline values at the nine-month follow-up, and were even lower at the 15-month follow-up for concerns about falling (median 26 vs. 26 points), walking performance (changes of −0.02 to 0.04 m/s), and physical function (mean 44.0 vs. 42.9 points). The control group remained unchanged throughout the study period. Conclusions: This balance-training programme reduced concerns about falling, and also improved gait in older adults with osteoporosis and increased risk of falling in a long-term perspective – important issues for fall prevention.
  •  
12.
  • Halvarsson, A, et al. (author)
  • Long-term effects of new progressive group balance training for elderly people with increased risk of falling - a randomized controlled trial
  • 2013
  • In: Clinical rehabilitation. - : SAGE Publications. - 1477-0873 .- 0269-2155. ; 27:5, s. 450-458
  • Journal article (peer-reviewed)abstract
    • To evaluate the long-term effects of a progressive and specific balance group-based program in healthy elderly individuals with increased risk of falling. Design: Follow-up of a randomized controlled trial at nine and 15 months on a population that has previously been described at three months. Setting: The study was conducted in Stockholm, Sweden. Subjects: 59 community-dwelling elderly (age 67–93 years), recruited by advertisement, were randomly allocated to training or to serve as controls. Intervention: Group balance training three times per week during 12 weeks with a 15 month follow-up time. Main measures: Participants were assessed at baseline, three, nine, and 15 months thereafter for gait function (preferred and fast walking), rapid step execution (single and dual task), fear of falling, and likelihood of depression. Results: Fast gait speed ( p = 0.004), dual task step execution ( p = 0.006) and fear of falling ( p = 0.001) were still improved in the training group at nine months follow-up. Only self-perceived fear of falling remained significantly improved ( p = 0.012) at 15 months follow-up. Although fast gait speed had decreased to baseline level in the training group (1.49 m/s) it remained significantly higher than in the control group (1.37 m/s) at the end of the study, a difference between the groups that was not seen at baseline. Conclusion: This training program provided important positive short and long-term benefits to gait, balance function, and fear of falling.
  •  
13.
  •  
14.
  •  
15.
  • Halvarsson, A, et al. (author)
  • Taking balance training for older adults one step further: the rationale for and a description of a proven balance training programme
  • 2015
  • In: Clinical rehabilitation. - : SAGE Publications. - 1477-0873 .- 0269-2155. ; 29:5, s. 417-425
  • Journal article (peer-reviewed)abstract
    • To give the rationale and evidence for and a detailed description of a rehabilitation programme of proven effectiveness in improving balance in older adults. Background theory and evidence: Based on the knowledge that balance loss usually occurs in situations when attention is divided, especially when being older, and that balance control relies on the interaction of several physiological systems, we have developed a specific and progressive balance training programme with dual- and multi-task exercises for older adults. Practical application: Balance demanding exercises, specific to the various components of balance control and to situations in daily life, were performed in sitting, standing and walking at three different levels of progression (basic, moderate and advanced) of increasing difficulty and complexity. The training was performed in 45-minutes group sessions, with 6–10 participants in each group, three times per week during 12 weeks, with two or three physiotherapists present. Conclusions: This balance training programme strengthens self-efficacy in balance control leading to improved fall-related self-efficacy, reduced fear of falling, increased walking speed, and improved physical function. Participants found the programme motivating, valuable, fun, and enjoyable, which was reflected in a high attendance rate.
  •  
16.
  •  
17.
  • Mitchell, Jonathan S., et al. (author)
  • Genome-wide association study identifies multiple susceptibility loci for multiple myeloma
  • 2016
  • In: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 7
  • Journal article (peer-reviewed)abstract
    • Multiple myeloma (MM) is a plasma cell malignancy with a significant heritable basis. Genome-wide association studies have transformed our understanding of MM predisposition, but individual studies have had limited power to discover risk loci. Here we perform a meta-analysis of these GWAS, add a new GWAS and perform replication analyses resulting in 9,866 cases and 239,188 controls. We confirm all nine known risk loci and discover eight new loci at 6p22.3 (rs34229995, P = 1.31 x 10(-8)), 6q21 (rs9372120, P = 9.09 x 10(-15)), 7q36.1 (rs7781265, P = 9.71 x 10(-9)), 8q24.21 (rs1948915, P = 4.20 x 10(-11)), 9p21.3 (rs2811710, P = 1.72 x 10(-13)), 10p12.1 (rs2790457, P = 1.77 x 10(-8)), 16q23.1 (rs7193541, P = 5.00 x 10(-12)) and 20q13.13 (rs6066835, P = 1.36 x 10(-13)), which localize in or near to JARID2, ATG5, SMARCD3, CCAT1, CDKN2A, WAC, RFWD3 and PREX1. These findings provide additional support for a polygenic model of MM and insight into the biological basis of tumour development.
  •  
18.
  •  
19.
  • Roaldsen, KS, et al. (author)
  • Task-specific balance training improves self-assessed function in community-dwelling older adults with balance deficits and fear of falling: a randomized controlled trial
  • 2014
  • In: Clinical rehabilitation. - : SAGE Publications. - 1477-0873 .- 0269-2155. ; 28:12, s. 1189-1197
  • Journal article (peer-reviewed)abstract
    • To evaluate the effects of a 12-week balance training programme on self-assessed function and disability in healthy community-dwelling older adults with self-perceived balance deficits and fear of falling. Design: A prospective, randomized controlled trial. Setting: Stockholm County, Sweden. Participants: A total of 59 community-dwelling older adults (42 women and 17 men) aged 67–93 were randomized to either an intervention group ( n = 38) or to serve as controls ( n = 21) after baseline testing. Intervention: The intervention was a 12-week, three times per week, progressive, specific and individually adjusted group balance-training programme. Main measures: Self-perceived function and disability measured with Late Life Function and Disability Instrument. Results: The intervention group reported improvement in overall function ( p = 0.016), as well as in basic ( p = 0.044) and advanced lower extremity function ( p = 0.025) compared with the control group. The study showed no improvement in overall disability or upper extremity function. Conclusion: This group balance training programme improves self-assessed function in community-dwelling older adults with balance deficits and fear of falling.
  •  
20.
  •  
21.
  •  
22.
  •  
23.
  • Chyrkin, A., et al. (author)
  • Effect of thermal cycling on protective properties of alumina scale grown on thin Haynes 214 foil
  • 2015
  • In: Corrosion Science. - : Elsevier BV. - 0010-938X. ; 98, s. 688-698
  • Journal article (peer-reviewed)abstract
    • The isothermal and cyclic oxidation of a thin alloy 214 foil (130μm thick) has been studied in air at 1200°C for up to 720 h. Haynes 214 forms a duplex oxide scale consisting of pure, columnar alumina overlaid by mixed Ni(Al,Cr)2O4 spinel with minor inclusions of (Al,Cr)2O3. A transition from external alumina to chromia scaling (abbreviated as TACS) occurs at the oxide-alloy interface after the Al reservoir of the foil is exhausted due to oxidation. The tensile cracking of the oxide scale upon thermal cycling is shown to promote the early transition from protective to accelerated breakaway oxidation. © 2015 Elsevier Ltd.
  •  
24.
  •  
25.
  •  
26.
  • Cortazar-Chinarro, Maria, et al. (author)
  • Association between the skin microbiome and MHC class II diversity in an amphibian
  • 2024
  • In: Molecular Ecology. - : John Wiley & Sons. - 0962-1083 .- 1365-294X. ; 33:1
  • Journal article (peer-reviewed)abstract
    • Microbiomes play an important role in determining the ecology and behaviour of their hosts. However, questions remain pertaining to how host genetics shape microbiomes, and how microbiome composition influences host fitness. We explored the effects of geography, evolutionary history and host genetics on the skin microbiome diversity and structure in a widespread amphibian. More specifically, we examined the association between bacterial diversity and composition and the major histocompatibility complex class II exon 2 diversity in 12 moor frog (Rana arvalis) populations belonging to two geographical clusters that show signatures of past and ongoing differential selection. We found that while bacterial alpha diversity did not differ between the two clusters, MHC alleles/supertypes and genetic diversity varied considerably depending on geography and evolutionary history. Bacterial alpha diversity was positively correlated with expected MHC heterozygosity and negatively with MHC nucleotide diversity. Furthermore, bacterial community composition showed significant variation between the two geographical clusters and between specific MHC alleles/supertypes. Our findings emphasize the importance of historical demographic events on hologenomic variation and provide new insights into how immunogenetic host variability and microbial diversity may jointly influence host fitness with consequences for disease susceptibility and population persistence.
  •  
27.
  • Davis, Paul A., et al. (author)
  • Alpine Ski Coaches' and Athletes' Perceptions of Factors Influencing Adaptation to Stress in the Classroom and on the Slopes
  • 2019
  • In: Frontiers in Psychology. - : FRONTIERS MEDIA SA. - 1664-1078. ; 10
  • Journal article (peer-reviewed)abstract
    • Research examining the student-athlete experience proposes a number of factors that can be both sources of stress and/or support. The dual career pathway offers a number of potential positive outcomes including psychological, social, and financial benefits; however, challenges including time management, fatigue, and restricted social activities are well documented. In consideration of the multidimensional student-athlete experience and the numerous factors that influence the complexity of potential stress, a mixed methods research study design was used in the study. First, data collected from surveys completed by 173 elite junior alpine skiers were analyzed to identify the degree to which athletes report experiencing stress associated with specific aspects pertaining to training, life, and organizational factors. These factors were then explored through semi-structured interviews with six coaches at the associated national elite sport schools. Taken collectively, athletes' reports of psychophysiological training stress on the Multidimensional Training Distress Scale were low. Scores on the college studentathletes' life stress scale revealed very low levels of general life stress; although the subscales associated with "performance demand" and "academic requirements" scored marginally higher. Scores on the Organizational Stressor Indicator for Sport Performers indicated low levels of organizational stress. The interviews with coaches elucidated the underlying factors potentially influencing athletes' positive adaptations to stress as they reported programming a number of strategies to reduce negative outcomes. Coaches aimed to teach athletes self-awareness and regulation strategies through the use of the training diaries and ongoing communication to promote positive adaptation to stress. A number of coaches also worked with sport psychology consultants to optimize athletes' training and study situations. Traditionally, research has noted high levels of stress in student-athletes due to co-occurring demands (school & sport); however, the data in the present study suggests that optimizing support mechanisms across domains can promote positive adaptations to potential sources of stress.
  •  
28.
  • Eklund, Jörgen, et al. (author)
  • Lean implementation, work environment and sustainability
  • 2015
  • In: Sustainable Development in Organizations. - : Edward Elgar Publishing. - 9781784716882 ; , s. 29-41
  • Book chapter (peer-reviewed)abstract
    • Lean is introduced in industry as well as in the public sector. Previous research has criticized Lean for creating bad working conditions. Also sustainability of organizational changes is claimed to be low. The aim of this chapter is to describe consequences for working conditions and sustainability as a result of implementations of Lean in manufacturing industry and in the public sector. A second aim is to give examples of the type of knowledge produced in an interactive research approach and to discuss the use of interactive research when implementing Lean. Two programs for implementing Lean were assessed through interactive research. The research showed that there is a huge variation between organizations regarding how Lean is interpreted, how it is implemented, and also regarding the outcomes. The majority of the employees in the manufacturing companies experienced that Lean meant improved working conditions, e.g. more participation, learning and development. However they also experienced more stress and repetitive work. For the public organizations, the employees experienced on average that the working conditions had deteriorated. Sustainability of the changes was also substantially lower than for the manufacturing companies. The interactive research approach enabled deep access to a broad sample of organizations and contributed to better relevance and validity of the research results.
  •  
29.
  • Eklund, Jörgen, et al. (author)
  • Sustainability and development of Lean implementations
  • 2014
  • In: Human Factors in Organizational design and management - XI. ; , s. 165-169
  • Conference paper (peer-reviewed)abstract
    • Lean production has become a major change strategy in Swedish public organizations. The aim of this paper was to identify factors that support or counteract sustainability and development of Lean implementations in public organizations. In an interactive research project including interviews and questionnaires, seven public organizations were followed during a three year period. Some factors supported and other factors counteracted sustainability and development of Lean. In conclusion, lack of sustained change was to a  large extent due to replacement of the top managers in five of the organizations and introduction of another change philosophy, low political and managerial ownership and financial problems.
  •  
30.
  • Esmaily, Mohsen, 1987, et al. (author)
  • Microstructural characterization of the Mg-Al alloy AM50 produced by a newly developed rheo-casting process
  • 2014
  • In: Materials Characterization. - : Elsevier BV. - 1044-5803 .- 1873-4189. ; 95, s. 50-64
  • Journal article (peer-reviewed)abstract
    • The microstructure of rheo-cast Mg-Al alloy AM50 produced by the RheoMetal process is investigated and compared with the same alloy produced by conventional high pressure die casting. The size and arrangement of microstructural constituents and pores are characterized quantitatively using image analyzing techniques. The nearest neighbor distribution of the intermetallic particles is determined. The area fraction of porosity in rheo-cast AM50 is about half that found in the high pressure die cast alloy. In rheo-cast material, the distribution of p phase (Mg17Al12) is relatively uniform throughout the cast. In contrast, the beta phase particles tend to form macroscopic agglomerates in high pressure die cast material. The externally solidified grains in the rheo-cast material exhibit a smaller aluminum gradient than in the high pressure die cast alloy. This indicates that the solidification of the rheo-cast material is closer to equilibrium.
  •  
31.
  •  
32.
  •  
33.
  •  
34.
  •  
35.
  • Kariminejad, A., et al. (author)
  • TOR1A variants cause a severe arthrogryposis with developmental delay, strabismus and tremor
  • 2017
  • In: Brain. - : Oxford University Press (OUP). - 0006-8950 .- 1460-2156. ; 140:11, s. 2851-2859
  • Journal article (peer-reviewed)abstract
    • Autosomal dominant torsion dystonia-1 is a disease with incomplete penetrance most often caused by an in-frame GAG deletion (p.Glu303del) in the endoplasmic reticulum luminal protein torsinA encoded by TOR1A. We report an association of the homozygous dominant disease-causing TOR1A p.Glu303del mutation, and a novel homozygous missense variant (p.Gly318Ser) with a severe arthrogryposis phenotype with developmental delay, strabismus and tremor in three unrelated Iranian families. All parents who were carriers of the TOR1A variant showed no evidence of neurological symptoms or signs, indicating decreased penetrance similar to families with autosomal dominant torsion dystonia-1. The results from cell assays demonstrate that the p.Gly318Ser substitution causes a redistribution of torsinA from the endoplasmic reticulum to the nuclear envelope, similar to the hallmark of the p.Glu303del mutation. Our study highlights that TOR1A mutations should be considered in patients with severe arthrogryposis and further expands the phenotypic spectrum associated with TOR1A mutations.
  •  
36.
  •  
37.
  •  
38.
  • Mortazavi, A. N., et al. (author)
  • Exploring failure modes of alumina scales on FeCrAl and FeNiCrAl alloys in a nitriding environment
  • 2020
  • In: Acta Materialia. - : Elsevier BV. - 1359-6454. ; 201, s. 131-146
  • Journal article (peer-reviewed)abstract
    • Two high-temperature FeCrAl and FeNiCrAl alloys were exposed in a strongly nitriding environment at 900 °C and the morphology of nitridation was studied. Quasi-in-situ experiments revealed that nitridation started at specific surface sites directly related to the alloy microstructure where the alumina scale was permeable to nitrogen. FeCrAl alloy grains with (112) orientation formed outward-growing alumina scales and were susceptible to nitridation. Outward-growing scales and substrate nitridation was also observed at chromium carbide precipitates in the FeNiCrAl alloy. Both alloys suffered nitridation at reactive element-rich (Y and Zr) inclusions larger than a certain critical size. The latter type of attack is caused by cracks and pores in the scale. The findings open new avenues of research for developing the next generation of high temperature alloys with superior properties.
  •  
39.
  •  
40.
  •  
41.
  • Shahabi-Navid, M., et al. (author)
  • Localized Atmospheric Corrosion of Magnesium-Aluminum Alloys Produced by Semisolid Casting: A 2D and 3D Investigation
  • 2021
  • In: Corrosion. - : NACE International. - 0010-9312 .- 1938-159X. ; 77:2, s. 242-253
  • Journal article (peer-reviewed)abstract
    • The localized corrosion of the two magnesium-aluminum alloys AM50 and AZ91 produced by a semisolid casting method was investigated under atmospheric corrosion conditions, in the presence of NaCl. Gravimetry confirmed the beneficial effect from ambient levels of carbon dioxide (CO2) in suppressing corrosion through the formation of magnesium hydroxy carbonates. Both 2D and 3D characterization revealed that ambient CO2 has a strong influence on the morphology and rate of localized corrosion. In CO2-free atmosphere, the alloys suffered localized corrosion resulting in clustered and interconnected cavities that extended deep into the material. In contrast, corrosion in the presence of ambient levels of CO2 (400 ppm) resulted in evenly distributed shallow corrosion sites. The results indicate that CO2 neutralizes the cathodic areas resulting in diminished cathodic activity and inhibiting NaCl(aq) droplet coalescence.
  •  
42.
  • Shoja, S., et al. (author)
  • Enhanced steel machining performance using texture-controlled CVD alpha-alumina coatings : Fundamental degradation mechanisms
  • 2024
  • In: International Journal of Machine Tools and Manufacture. - 0890-6955. ; 197
  • Journal article (peer-reviewed)abstract
    • Cemented carbide inserts coated with CVD α-alumina, particularly those exhibiting a (0001) texture, have proven highly effective in steel turning. Despite the established superior performance of (0001) textured alumina coatings, the underlying reasons remain unclear. This study explores the influence of the crystallographic texture of alumina on wear mechanisms in various chip-tool contact zones on the insert rake face. The objective is to establish a fundamental understanding of the active degradation mechanisms and machining performance by relating coating texture to the orientation and deformation of individual Al2O3 grains. Two multilayered coatings, Al2O3 on Ti(C,N), featuring (0001)- and (112‾0)-textured CVD α-alumina, were assessed in dry turning of a bearing steel. The wear rate of the (112‾0) coating was double that of the (0001) coating. Worn coatings exhibit nano-terrace formation at the insert edge, likely due to chemical etching. In the sticking zone, plastic deformation leads to larger facets for grains oriented with the chip flow direction, while rounded surfaces result if this condition is not met. In the transition zone, both (0001) and (112‾0) textured coatings undergo increased plastic deformation accompanied by sub-surface dislocations. (0001) texture deforms more by basal slip creating a wavy coating pattern with steps present at larger misalignments of the lattice planes in neighboring grains while (112‾0) texture deforms by several slip systems creating elongated ridges and ruptured-like areas resulting in rougher surface. This difference in surface morphology is then inherited by the abrasion of submicron coating fragments embedded in the chip (more in (112‾0) texture) in the sliding zone resulting in an even rougher surface. Chemical reaction with the hot chip may also contribute to wear acting as an additional mechanism. This fundamental understanding contributes to the potential enhancement of steel machining using texture-controlled CVD alumina coatings, ultimately improving coated cutting tool performance.
  •  
Skapa referenser, mejla, bekava och länka
  • Result 1-42 of 42
Type of publication
journal article (33)
conference paper (7)
reports (1)
book chapter (1)
Type of content
peer-reviewed (36)
other academic/artistic (6)
Author/Editor
Franzen, E (6)
Olsson, E (4)
Turesson, I (3)
Eklund, Jörgen (3)
Nahi, H (3)
Hemminki, K (3)
show more...
Johansson, Lars-Gunn ... (3)
Langer, C. (3)
Goldschmidt, H (3)
Waage, A (3)
Weinhold, N (3)
Svensson, Jan-Erik, ... (3)
Oddsson, L (3)
Ali, M (2)
EASTON, D (2)
Hansson, M (2)
Hansson, Markus (2)
Hoffmann, P (2)
Sud, A (2)
Nothen, MM (2)
Pettersson, A (2)
Nilsson, Björn (2)
Swerdlow, A (2)
Muir, K (2)
Peto, J (2)
Gullberg, Urban (2)
Nilsson, B (2)
Pharoah, P (2)
Försti, Asta (2)
Hemminki, Kari (2)
Kuiper, R (2)
Kote-Jarai, Z (2)
Canzian, F (2)
Pashayan, N (2)
Eeles, RA (2)
Li, N (2)
Thomsen, H (2)
Ali, Mina (2)
Wihlborg, Anna-Karin (2)
Johnsson, Ellinor (2)
Stephens, OW (2)
Mellqvist, UH (2)
Johnsson, E (2)
Gullberg, U (2)
Thorleifsson, G (2)
Thorsteinsdottir, U (2)
Stefansson, K (2)
Chen, BW (2)
Kimber, S (2)
Kristinsson, SY (2)
show less...
University
Karolinska Institutet (26)
Lund University (5)
Chalmers University of Technology (5)
Royal Institute of Technology (3)
Uppsala University (3)
University of Gothenburg (2)
show more...
Högskolan Dalarna (2)
Umeå University (1)
Linköping University (1)
Jönköping University (1)
University of Skövde (1)
RISE (1)
Swedish University of Agricultural Sciences (1)
Red Cross University College (1)
show less...
Language
English (41)
Swedish (1)
Research subject (UKÄ/SCB)
Medical and Health Sciences (8)
Engineering and Technology (7)
Social Sciences (3)
Natural sciences (2)

Year

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Close

Copy and save the link in order to return to this view