Ben' V. Enhancement of bearing capacity of gas-turbine engine blades made of titanium alloys by complex final machining.

The research work is devoted to the problem of enhancement of bearing capacity of engines TV3-117i and TV3-117VMA-SBM1 compressor Stage 1 blades made of titanium alloys BT8M and BT8 with the use of forming rational combination of properties of the surface layer by complex final machining. The new solution of the science problem of erosion resistance enhancement and assurance of specified parameters of durability and impact strength of the com-pressor blades made of titanium alloy is obtained and lies in forming favorable com-bination of the parameters by complex final machining. The comprehensive analysis of the blade stress-stained condition at oscillation according to the first flexural mode and residual stressed condition of the surface layer is performed. It is ascertained that maximum stress level at the leading edge is equal to 95% of the stress level at the blade pressure surface. Mathematical formulas for evaluation of impact strength of the compressor blades hardened by the plastic surface deformation, taking into account local plastic deformations, are obtained. The above formulas testify to the positive effect of resid-ual compressive stresses and enable calculation of permissible level of bending stress in the critical section and strength margin at the impingement against foreign body. It is ascertained that complex machining results in the significant increase in the compressor blades bearing capacity as a result of formation of favorable combi-nation of the surface layer characteristics due to increase in wear resistance, endur-ance and impact strength. Production process recommendations for selection of efficient conditions of IPN+PSBH are developed and used for manufacture of blades at Motor Sich JSC.