引线框架用Cu-Cr-Zr-Mg合金的加工工艺与性能研究

【作者】 傅声华；

【导师】 柳瑞清；

【作者基本信息】 江西理工大学 ， 材料加工工程， 2009， 硕士

【摘要】 引线框架材料在集成电路中起着固定芯片,保护内部元件,传递电信号并向外部散发热量的作用,是基础电路的关键部件,而作为引线框架材料用Cu-Cr-Zr合金,由于其能通过合理的形变热处理工艺改善组织、性能而获得高强高导性能,从而成为最具发展潜力的高性能铜合金材料。如何在非真空环境下熔铸获得质量良好的合金一直是业内研究的难点,本文主要探讨在大气环境中通过合理的熔铸工艺获得良好的铸态Cu-Cr-Zr组织,分析热轧时铸锭加热温度分别为850℃、900℃及热轧变形量70%～80%对热轧后的组织性能影响,设计单因素实验,分析了一次、二次时效前后冷变形量对时效后性能的影响。通过七因素三水平正交实验,考察各因素对Cu-Cr-Zr合金的组织、性能的影响,并确定其影响因子的主次关系,优化实验参数得出最佳加工工艺。研究结论如下:(1)在大气环境下熔铸Cu-0.45Cr-0.15Zr-0.05Mg合金,熔炼温度1250℃,保温时间15～20 min,浇铸温度1150～1200℃,浇铸出来的铸锭质量较好。(2)热轧铸锭加热温度为900℃×1h,热轧总加工率为70%对材料力学性能较好,组织中有少量第二相呈点或短条状,并沿晶界分布。(3)实验表明一、二次时效前冷变形均能不同程度地促进时效,冷变形量越大,第二相析出速度越快。时效后冷变形对降低电导率的影响较小,对提高抗拉强度的影响较大。(4)通过正交实验的数据分析,影响电导率的主要因素是一次时效温度,其次是二次时效时间和一次时效时间,影响抗拉强度的主要因素是二次时效时间,其次是一次时效时间和二次冷轧加工率。通过综合分析得出最佳工艺方案:热轧75%+固溶950℃×60min+一次冷轧70%+一次时效600℃×1.5h+二次冷轧50%+二次时效520℃×4h。更多还原

【Abstract】 Lead frame materials play a very important role in IC.They can support chip, protect inside component, transmit the electric signal, and send out the heat of the componet outwards, it is a key part of base IC. Making Cu-Cr-Zr alloys for Lead frame materials, because it can improve structure and properties through reasonable cold-working and heat treatment to get high strength and high conductivity properties, so that become most potencial high properties copper alloy materials.How to get copper alloy of good quality is always a difficulty in our field in unvacuum environment.The main idea in this thesis is to get good Cu-Cr-Zr alloy casted by reasonable melting and casting technique in atmosphere,analyse influence of temperature of hot-rolling 850℃,900℃and the degree of hot deformation 70%～80% for constructure and properties after hot rolling,design experiments of single factor,analysing for the influence of the degree of cold deformation for aging properties before and after the first time and the second time aging.Discussing the influence of each factor for properties of Cu-Cr-Zr alloy by L18(37)orthogonal test,making sure primary and secondary order of its influence factors, optimize experiment parameters to get the optimum process.The following is the study conclusions:(1)The quality of casting Cu-0.45Cr-0.15Zr-0.05Mg alloy is better when the temperature of melting is 1250℃,the time of heat preservation is in 15～20 min , the temperature of casting is in 1150～1200℃in atmosphere.(2)The temperature of hot-rolling is 900℃×1h,the degree of deformation of hot-rolling is better to material properties, when it is 75% , there is a little the second phase with dot or short strip shape which disperse along boundary of grain.(3)The experiments show that the first and second cold deformation improve aging to different extent,the larger the degree of cold deformation is the faster another phase separate out. Cold deformation has smaller influence over reducing electric conductivity after aging, while has larger influence over increasing tensile strength.(4)After orthogonal test, the main factors of influence for conductivity are the temperature of the first aging, the time of the second aging and the time of the first aging, the main factors of influence for tensile strength are the time of the second aging , the time of the first aging and the degree of the second cold rolling. This paper can get the optimum process by comprehensive analysis : hot rolling(75%)+solution (950℃×1h) +the first cold rolling (70%)+the first aging (600℃×1.5h)+the second cold rolling (50%)+the second aging(520℃×4h).更多还原