【摘要】 用热塑性试验评定2219铝合金的液化裂纹敏感性,利用扫描电镜对热塑性试样断口进行了分析。结果发现:α(Al)-CuAl2离异共晶熔点高于α(Al)-CuAl2共晶;加热过程中α(Al)-CuAl2离异共晶后熔化,冷却过程中离异共晶先凝固结晶,因此2219铝合金脆性温度区间较窄;α(Al)-CuAl2离异共晶的凝固结晶使合金在高温下迅速恢复强度和塑性,使2219铝合金液化裂纹敏感性低,焊接性好。更多还原

【Abstract】 Hot ductility testing was used to evaluate the liquation cracking susceptibility of aluminum alloy 2219. The fracture surface of hot ductility samples was examined using SEM. The melting point of α(Al)-CuAl2 divorced eutectic was higher than that of α(Al)-CuAl2 eutectic . The melting of α(Al)-CuAl2 eutectic was prior to the α(Al)-CuAl2 divorced eutectic in heating process, but solidification of α(A)-CuAl2 divorced eutectic was prior to the α(Al)-CuAl2 eutectic in cooling process, so the brittle temperature range BTR of aluminum alloy 2219 was narrow. α(Al)-CuAl2 divorced eutectic solidification in cooling process made the alloy rapidly recover the strengh and ductility, which caused aluminum alloy 2219 not being susceptible to liquation cracking and having good weldability.更多还原