摘要
研制一种Mg-Zn-Al-Er钎料。在钎料熔炼的过程中,对处于液态金属的钎料进行超声振动,超声功率为600 W,超声频率为20 kHz,超声处理时间为分别为0 s、60 s、120 s、180 s及240 s。钎料浇铸温度为600℃。研究结果表明,在液态钎料中施加超声波,可以起到净化钎料、细化晶粒及促进第二相α-Mg和Al3Er析出的作用。研制的Mg-Zn-Al-Er钎料的熔点不超过355℃,熔化区间不超过10℃,有利于钎焊的进行。对所研制的钎料进行炉中钎焊。钎焊过程中,熔点较高的Al3Er相仍可弥散分布于钎焊接头中,作为形核质点,细化晶粒。钎料超声处理时间为180 s时,其钎焊搭接接头剪切强度为59.7 MPa,为未经超声处理钎料搭接接头剪切强度的1.2倍。
An Mg-Al-Zn-Er filler metal is developed.During the melting of filler metal,ultrasonic vibration is applied to the liquid metal.The power of ultrasonic is 600 W,the frequency of ultrasonic is 20 kHz,and the ultrasonic vibration time is 0-240 seconds.The liquid filler metal is casting under 600 ℃.The experiment results show that the melting points of developed filler metal do not exceed 355 ℃ and the melting range is not beyond 10 ℃,which benefit for the soldering.The ultrasonic vibration acting on the melting filler metal has the effect of purifying microstructure,refining the grain and accelerating the precipitation ofα-Mg and Al3Er.During the soldering of AZ31 magnesium alloy,the Al3Er precipitation phase act as nucleation site,preventing the coarsening of crystal grain.When the ultrasonic vibration time of solder is approaching 180 s,the shear strength of lapping joint is 59.7 MPa,which is almost one point two times that of the filler metal which has not undergo ultrasonic treatment.
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2014年第6期70-74,共5页
Journal of Mechanical Engineering
基金
国家自然科学基金资助项目(51275008)
