改型GH4133A合金长期时效的性能稳定性研究

对经过标准热处理改型GH4133A合金,在650、700和750℃进行长时间的时效处理,测量其室温拉伸和冲击性能、硬度、400℃拉伸性能和在750℃/343 MPa条件下持久性能.结果表明:在650℃和700℃下时效时,合金的性能变化规律一致,性能具有良好的稳定性.而在750℃时效时,合金的室温拉伸和400℃拉伸性能在时效500 h以前保持稳定,500 h以后随时效时间的增长而下降;合金的室温冲击性能在时效300 h以前保持稳定,300 h后下降;合金在750℃/343 MPa条件下,在时效600 h以前,持久性能寿命很稳定,基本保持在100 h左右,时效600 h以后的持久寿命迅速下降.

Study on stability of mechanical properties for modified GH4133A alloy after long-term aging

Mechanical properties of a modified GH4133A alloy after standard heat treatment followed by long time aging treatment at 650 ℃,700 ℃ and 750 ℃ respectively were tested at room temperature and high temperature.The results indicated that the change of the tensile and impact property at room temperature,the hardness,the tensile property at 400 ℃ and stress-rupture life at 750 ℃/343 MPa is identical,and mechanical properties stability is good in the modified GH4133A alloy after long-term aging at 650 and 700 ℃.On the other hand,when the aging temperature is 750 ℃,the tensile properties at room temperature and 400 ℃ are steady before 500 h aging,and then decrease with the aging time from 500 h to 2 000 h.The impact property is steady before 300 h aging,and it begins to decrease after 300 h.The stress-rupture life at 750 ℃/343 MPa is steady before 600 h aging,the value is about 100 h,and then reduces distinctly with the aging time from 600 h to 2 000 h.