Mechanical and tribological properties of “substrate–material” multifunctional composite with shape memory effect

Resumo

The properties of steel–TiNi, TiNiCu, NiAl alloy multifunctional composite with shape memory effect are studied. The system is obtained under high-energy exposure (argon arc and laser surfacing, plasma and high-rate gas flame sputtering) with the formation of a structure with fine-grained to nanoscale dispersity. The experimental studies reveal the efficiency of the elaborated technique of the synthesis of composites to increase the wear resistance, fatigue strength, and endurance at frictionally cyclic low-cycle loading of material. The increase in fatigue and wear characteristics are explained by the processes caused by the combined cyclic loading and reverse friction. As is shown, the friction and mechanical fatigue in a surface-modified layer of the material undergoing the shape memory effect in the friction domain causes an increase in temperature that favors the martensite–austenite transformation, whereas the pressure arising in friction induces the transformation plasticity effect owing to the formation of stress martensite.