超声振动对5356铝合金组织及力学性能的影响

Effect of ultrasonic vibration on microstructure and mechanical properties of 5356 aluminum alloy

为探究超声振动对5356铝合金组织与性能的影响,改变变幅杆插入深度、超声处理时间等工艺制备出5356铝合金,通过对显微组织与断口形貌的观察、密度和室温力学性能的测试研究了5356铝合金超声处理对组织性能的影响,试验结果表明:未加超声处理的5356铝合金组织中存在大量的树枝晶,还有许多杂质包括氧化物夹杂。熔体超声处理后的5356铝合金晶粒组织均匀,大部分杂质被除去。当熔体温度为720℃,变幅杆插入深度30mm,超声处理时间2～5min时,5356铝合金力学性能最好,铸锭抗拉强度为225MPa,比未加超声处理试样提高7.1%,伸长率为11.7%,提高了52%,密度达到2.598g·cm-3。

In order to investigate the influence of ultrasonic vibration on the microstructure and properties of 5356 aluminum alloy,the 5356 aluminum alloy has been prepared by changing the insertion depth of horn and ultrasonic treatment time.Through the testing of microstructure and fracture morphology,density and room temperature mechanical properties,the influence of ultrasonic vibration on the microstructure and properties of 5356 aluminum alloy have been studied.The experimental results show that there are a large number of dendrites and many impurities including oxide inclusions in the 5356 aluminum alloy without ultrasonic treatment.The 5356 aluminum alloy after melt ultrasonic treatment has a uniform grain structure,most impurities of which have been removed.When the melt temperature is 720℃while the horn insertion depth is 30mm and the ultrasonic treatment time is 2~5min,the mechanical properties of 5356 aluminum alloy are the best.The tensile strength of the ingot is 225MPa,which is 7.1%higher than that without ultrasonic treatment.The elongation rate is 11.7%which increases by 52%,and the density reaches 2.598g·cm^-3.