4. Conclusions


characteristics. In addition, vice versa for each depth of hardened zone, the optimal level of surface hardening exists. Furthermore, it can be forecasted that for each alloy the optimal relation between parameters K and l exists that provides absolutely maximal gain of fatigue strength. Such parameters of gas-saturated layers can be determined as optimal parameters of alloy hardening. The aim of the next step lies in the search of the optimal level of K and l parameters of the hardened zone.

Fatigue strength of titanium alloy VT5, under rotating bending conditions, as a function of depth of hardened

Fatigue strength of titanium alloy VT5, under rotating bending conditions, as a function of level of surface hardening when depth of hardened zone (gas saturated) is constant: (1) l = 30–35 μm (2) l = 60–65 μm.

Fatigue curves of titanium alloy VT5, under rotating bending conditions, depending on level of surface hardening K, when depth of hardened (gas saturated) zone l is constant (a) l = 30–35 μm and (b) l = 60– 65 μm: (1) initial state K = 5%; l = 5–10 μm; (2) K = 32%; (3) K = 82%; (4) K = 34%; (5) K = 60%.

Titanium Alloys - Novel Aspects of Their Manufacturing and Processing

Figure 22.

Figure 21.

Figure 23.

100

zone, when level of surface hardening is constant K = 30%.

influence on the hardness of surface layer, but the depth of the hardened zone is being increased with the increasing of the temperature and exposure time.

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