Influence of Process Parameters on Reaction Products during Self-Propagating High-Temperature Synthesis of Porous NiTi

• NiTi is proposed to be a biomaterial suitable for bone replacements. Reactive synthesis, Self-Propagating High-Temperature Synthesis (SHS) of NiTi from Ni and Ti powder is a suitable method to produce porous structures to promote osseointegration. The influence of pressed density and ignition temperature on the reaction products formed is investigated. Porosity after pressing was 20%, 30% and 40 % and ignition temperatures were 400°C, 500°C and 600°C. The reaction products found were NiTi, as well as Ti2Ni and Ni3Ti, in addition to residual Ni and Ti. The amount of NiTi formed increases with ignition temperature, with a maximum at an initial porosity of 30% and ignition temperature of 600°C. This coincides with the minimum amount of residual Ni and Ti. The reaction imbalance is caused by the formation of Ti2Ni at high pressed densities and by a preferential nucleation of Ni3Ti, both suggested to be dominated by the effective contact area between the Ni and Ti particles after pressing.

Subject headings

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

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

Keyword

Bicmaterial

Ni

NiTi

Phase Selection

Reaction Synthesis

Ti

Reaction products

Density measurement (specific gravity)

High temperature effects

Ignition

Porosity

Porous materials

Reaction kinetics

Synthesis (chemical)

Publication and Content Type

ref (subject category)

art (subject category)