Simulation of phase evolution in a Zr-based glass forming alloy during multiple laser remelting

• Additive manufacturing by laser-based powder bed fusion is a promising technique for bulk metallic glass production. But, reheating by deposition of subsequent layers may cause local crystallisation of the alloy. To investigate the crystalline phase evolution during laser scanning of a Zr-based metallic glass-forming alloy, a simulation strategy based on the finite element method and the classical nucleation theory has been developed and compared with experimental results from multiple laser remelting of a single-track. Multiple laser remelting of a single-track demonstrates the crystallisation behaviour by the influence of thermal history in the reheated material. Scanning electron microscopy and transmission electron microscopy reveals the crystalline phase evolution in the heat affected zone after each laser scan. A trend can be observed where repeated remelting results in an increased crystalline volume fraction with larger crystals in the heat affected zone, both in simulation and experiment. A gradient of cluster number density and mean radius can also be predicted by the model, with good correlation to the experiments. Prediction of crystallisation, as presented in this work, can be a useful tool to aid the development of process parameters during additive manufacturing for bulk metallic glass formation.

Ämnesord

TEKNIK OCH TEKNOLOGIER  -- Materialteknik -- Bearbetnings-, yt- och fogningsteknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Materials Engineering -- Manufacturing, Surface and Joining Technology (hsv//eng)

TEKNIK OCH TEKNOLOGIER  -- Materialteknik -- Annan materialteknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Materials Engineering -- Other Materials Engineering (hsv//eng)

Nyckelord

Additives

Glass

Heat affected zone

High resolution transmission electron microscopy

Laser heating

Laser theory

Metals

Nucleation

Scanning electron microscopy

Zircaloy

(metallic) glass

Classical nucleation theory

Growth theory

Laser-based

Multiple lasers

Nucleation and growth

Phase evolutions

Phase transformation modelling

Powder bed

Simulation of laser-based powder bed fusion

Metallic glass

Solid Mechanics

Hållfasthetslära

Classical nucleation and growth theory

Metallic glass

Phase transformation modelling

Simulation of laser-based powder bed fusion

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)