摘要
自行研制了合金应力应变测试仪,并实测间接挤压铸造Al-5Cu合金凝固过程中应力、应变、温度的变化规律,得出应力、应变、温度三者之间的数学关系。结果表明:在温度降低到大约410℃时,在间接挤压铸造Al-5Cu合金内部将产生较大的"冲击"应力,由此提出了避免产生热裂的开模温度判定条件。Al-5Cu合金轴承保持架成形过程中保压15s开模,此时铸件温度425℃,略高于合金产生"冲击"应力的温度,可以使裂纹率降低到12.3%。
The variation rule of stress,strain and temperature of indirect squeeze-cast Al-5Cu alloy during solidification was measured by using self-developed testing apparatus,and the mathematical relations among them were obtained.The results showed that when temperature was below 410 ℃,a rather great impact stress would be generated inside the Al-5Cu alloy,and according to which,judgment rules of mold-opening temperature to avoid heat cracks were obtained.When dwell time reached 15 s during forming of bearing retainer casting,open the mold,when the temperature of casting was 425 ℃;a little higher than cracks-generating temperature,and the generating rate of heat cracks was reduced to 12.3%.
出处
《铸造》
CAS
CSCD
北大核心
2008年第4期350-353,共4页
Foundry
