Cu-P基非晶钎料的成分优化及其钎焊性能研究

发布时间：2018-04-10 20:12

  本文选题：Cu-P基非晶钎料 + 熔化特性　； 参考：《安徽工业大学》2017年硕士论文

【摘要】：本文概括描述了铜磷基钎料的性能特点及其在相关领域中的应用前景,同时也阐述了铜磷钎料在钎焊中面临的问题。为了降低成本并提高钎焊接头性能,本文对钎料进行成分优化以及钎焊工艺的改善。实验设计了五种不同成分的铜磷基钎料,通过单辊急冷设备制成非晶条带,以不等间隙代替等间隙的方式进行真空钎焊,并分析添加合金元素在促进形成非晶及改善接头性能方面的作用。为了全面了解Cu-P基非晶钎料的性能优点,本文将制备的非晶钎料和成分相同的传统钎料做比较试验。通过差示扫描量热方法(DSC)分析两种不同结构钎料在加热升温过程中的熔化性能。以真空环境下,加热熔化钎料在纯铜板表面的铺展范围来研究钎料对纯铜的润湿能力。对于真空条件下非晶钎料钎焊纯铜得到的接头,通过X射线分析(XRD)、扫描电镜分析(SEM)、金相显微分析以及纳米压痕测试等现代测试方法,研究添加元素和钎焊工艺等对接头组织结构和相关性能的作用。试验结果表明:Cu_(76)P_(140Ni_7Sn_3、Cu_(76)P_(14)Ni_8Sn_2、Cu_(75)P_(14)Ni_8Sn_3、Cu_(74)P_(14)Ni_8Sn_4、Cu_(74)P_(14)Ni_9Sn_3五种成分铜磷基钎料的非晶形成能力较强,且制备的薄带表面光滑、厚度均匀,能够对折180°不断裂,具有良好的柔韧性。其中以Cu_(75)P_(14)Ni_8Sn_3的综合性能最佳。在成分完全相同的情况下,铜磷基非晶钎料比晶态钎料的固、液相线低,且熔化温度范围更窄。合金元素Ni、Sn的添加,有利于钎料熔化范围的窄化。加热温度和保温时间对液态钎料的铺展润湿有很大的影响,铜磷基非晶钎料的铺展范围随加热温度和持续时间的增长而先升后降,且在660℃下保温12 min时铺展范围达到最大;而普通晶态钎料在相同条件下的铺展范围则一直呈现上升趋势。同样的钎焊工艺下,铜磷基非晶钎料对母材的铺展润湿作用比晶态钎料优越。铜磷基非晶钎焊料的焊后接头形成了良好的冶金结合,整个焊缝主要是由元素扩散区、钎料和母材相互作用的界面区以及钎料残余物组成的中心区三部分组织组成。扩散渗透区和界面区域基本由铜基固溶体组成,钎料残留中心区则主要由铜基固溶体和Cu-P、Ni-P脆硬化合物组成。整个焊缝的硬度从基体到焊缝中心,硬度逐渐升高,其中以钎料残留中心区的脆硬相硬度最高。钎焊得到的接头剪切强度随加热温度和保温持续时间的增加,表现出先增后减的趋向,其中不等间隙对接头力学性能起到明显的改善作用。试验中,以Cu_(75)P_(14)Ni_8Sn_3非晶钎料在670℃保温12 min下得到的接头强度最高,达到55 MPa。
[Abstract]:In this paper, the performance characteristics of copper-phosphorus based solder and its application prospect in related fields are described. At the same time, the problems faced by Cu-P filler metal in brazing are also described.In order to reduce the cost and improve the properties of brazing joint, the composition of brazing alloy and the improvement of brazing process are optimized in this paper.Five kinds of copper-phosphorus based solders with different compositions were designed experimentally. Amorphous strips were made by single roll quench equipment, and vacuum brazing was carried out by using unequal gap instead of equal gap.The effect of adding alloying elements on forming amorphous and improving the properties of joints was analyzed.In order to fully understand the properties and advantages of Cu-P based amorphous solder, a comparative test was made between the prepared amorphous solder and the traditional solder with the same composition.The melting properties of two kinds of brazing alloys with different structures during heating were analyzed by differential scanning calorimetry (DSC).The wetting ability of solder on pure copper was studied by using the spreading range of heating melting filler metal on the surface of pure copper plate in vacuum environment.For the joint of pure copper brazed by amorphous solder under vacuum condition, modern testing methods such as X-ray analysis, SEM analysis, metallographic microanalysis and nano-indentation test are used.The effects of adding elements and brazing technology on the microstructure and properties of joints were studied.Among them, the comprehensive performance of Cu_(75)P_(14)Ni_8Sn_3 is the best.When the composition is the same, the solid and liquid phase line of Cu-P based amorphous solder is lower than that of crystalline filler metal, and the melting temperature range is narrower.The addition of nio Sn is beneficial to narrow the melting range of solder.Heating temperature and holding time have great influence on the spreading and wetting of liquid solder. The spreading range of Cu-P based amorphous solder increases first and then decreases with the increase of heating temperature and duration, and reaches the maximum at 660 鈩，

本文编号：1732733