Mg对Sn-0.7Cu钎料组织及性能的影响

Effect of Mg on the Microstructure and Properties of Sn-0.7Cu Solders

研究了Mg元素对Sn-0.7Cu共晶钎料微观组织、熔化特性、润湿性能及力学性能的影响,结果表明:Mg元素的适量添加能细化钎料的共晶组织,过量添加时共晶组织消失,同时使Cu_(6)Sn_(5)颗粒由细小的颗粒状转变为短棒状。钎料的液相线温度随Mg含量的增加显著降低,当Mg含量为1.0%(质量分数)时,钎料的液相线温度降低到222.58℃,固液温度区间值不断增大,过冷度先增大后减小;钎料合金的润湿性随着Mg含量的增加呈先增大后减小的趋势,Mg含量为0.1%(质量分数)时,钎料合金的润湿性能最佳,铺展面积为85.74 mm^(2),相对于Sn-0.7Cu钎料提高了4.37%;Mg元素能够显著提高钎料的显微硬度,当Mg含量为1.0%(质量分数)时,钎料的显微硬度达到最大值,相对于Sn-0.7Cu提高了17.2%。

The effect of Mg element on the microstructure,melting characteristics,wettability and mechanical properties of Sn-0.7Cu eutectic solders were investigated.The results show that a proper addition of the Mg element refines the eutectic structure of the solders,while excessive addition results in the disappearance of the eutectic structure,and the transformation of Cu_(6)Sn_(5) from fine particles to short rods.The melting point of the solders decreases significantly with the increasing addition of Mg element and it decreases to 222.58℃with 1.0wt%Mg.The melting range increases and the degree of supercooling increases first and then decreases with the increasing addition of the Mg element.The wettability of sol-ders first increase and then decrease with the increase of Mg element.When the content of Mg element reaches to 0.1wt%,best wetting perfor-mance can be found with an spreading area of 85.74 mm^(2) and an increase by 4.37%compared with Sn-0.7Cu solder can be obtained.In addition,the microhardness of Sn-0.7Cu-x Mg solder can significantly increase with the addition of the Mg element and reached the maximum value at 1.0wt%Mg,increasing by 17.2%.