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High temperature creep, isothermal cyclic creep, and creep with additional thermal-mechanical fatigue stress component were performed on a wrought nickel base superalloy. The effect of the individual tensile hold periods as well as combined effect of hold periods and the thermo-mechanical fatique stress effect was studied. The deformation behaviour was compared with of static creep. The experimental results show that the introduction of tensile hold periods only to monotonic creep causes an increase in the fracture life proportional to the duration of the individual hold periods. An additional thermo-mechanical fatigue stress component produced by cooling at cyclic creep between the individual cycles resulted in more strain reduction and more pronounced strengthening.

Influences of high temperature creep were perfomed on a wrough nickel base super alloy. Results give, all fractures have characteristic intergranular crack initiation add propagation starting at spacimen surface. The resulting fracture mechanish for the crack propagation and the final rupture was gouerned by creep deformation.

The influence of severe plastic deformations on structural, mechanical and plastic properties of ARMCO – Fe in equal-channel angular pressing procedure was investigated. Mathematical simulations of stress and temperature fields were applied, too.