振动研磨工艺对QAl10-4-4合金的表面组织及性能的影响

Effect on the Microstructure and Surface Properties of the QAl10-4-4 Alloy by the Mechanical Vibration Polishing Treatment

研究了振动研磨工艺对涡轮用QAl10-4-4合金组织和表面性能的影响.结果表明:振动研磨处理后,QAl10-4-4合金产生了从研磨表面至心部硬度逐渐降低的硬化层,表面硬度提高约20%;相对于未研磨处理的QAl10-4-4合金,经振动研磨处理后,合金处于表面压应力状态,表面残余应力提高约300MPa,表面粗糙度明显降低,表面摩擦因数显著下降,耐磨性显著提高.工程实际应用结果表明:使用振动研磨工艺处理QAl10-4-4合金蜗轮提高整机的传动效率超过20%.振动研磨后,材料表面综合性能的提高与表层组织细化有直接关系.

This paper studies the effect on microstructure and surface properties of the QAl10-4-4 alloy via mechanical vibration polishing treatment（MVPT）. It is found that a hardened layer was present in the QAl10-4-4 alloy after MVPT and the hardness gradually decreases from the surface to the centre. The surface hardness increased by 20 %. Compared to the samples without MVPT, samples with MVPT has a compressive stress state, increased the surface residual stress by about 300 MPa, and reduced the surface roughness and surface friction coefficient greatly which led to increase the wear resistance. Practical applications indicates that mechanical efficiency increases more than 20 % by using the QAl10-4-4 alloy（with MVPT） worm wheel . The improvement of the comprehensive surface properties of the alloy with MVPT is directly associated with refinement of microstructures in the hardened layer.