Nickel-titanium alloys shaping and casting technology is difficult due to a high reactivity of titanium and brittleness in the as cast state. Therefore, powder metallurgy technology offering new technological possibilities and in addition controlled porosity was applied. Shape memory alloy was compacted from the prealloyed powder delivered by Memry SA showing M_s = 10^oC and A_s = -34^oC as results from DSC measurements. The hot compaction in the as delivered spherical particle’s statewas performed in a specially constructed vacuum press, at temperature of 680^oC and pressure of 400 MPa. The alloy powder was encapsulated in copper capsules prior to hot pressing to avoid oxidation or carbides formation. The alloy after vacuum high pressure and temperature of 680^oC compaction (i.e. above the NiTi stability range) has shown similar transformation range as the powder. The porosity of samples compacted in the as delivered state was only 1%. TEM studies shown  presence of small amount of B19' martensite and Ni₄Ti₃ particles at room temperature. The samples tested in compression up to ε = 0.06 have shown partial superplastic effect and returned back to ε = 0.01 after unloading. They have shown also high ultimate compression strength of 1600 MPa. Measurements of the samples temperature change during deformation allowed to detect temperature increase up to 2 degrees during loading and similar decrease during unloading.

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