感应—激光复合加热连接金刚石磨粒技术的基础研究

High percentage of abnormal failure of grits, which caused by thermal damage during brazing, is a severe issue in the field of brazed diamond and is urgently to be solved. Based on the causes of why current heating methods of brazing diamond cannot meet the quire of low thermal damage brazing, an induction-laser coupled heating is presented to braze diamonds with the aim of reducing thermal damage brazing diamonds as much as possible by coupling the two thermal fields. The key implement technical problems of the coupled heating will be studied and solved. The coupling law and regulation mechanism of the induction-laser coupled heating thermal field will be revealed. After those, the brazing of diamond by the coupled heating will be investigated. To solve problems of the poor fluidity of melted brazing alloy and the residual stress of brazed grits, the ultrasonic vibration will be employed to assist the coupled heating brazing process. The comprehensive investigation of brazing diamond by ultrasonic assistant induction-laser coupled heating will be carried out, during which the bonding mechanism and the interface actions of diamond/brazing alloy will also be studied. Meanwhile, the thermal damage on diamond of this new heating method will be evaluated. On the basis of studies mentioned above, the verification experiments will be carried out, in which, typical grinding discs will fabricated and their grinding ability will be investigated. All the work of this research project will be the reliable scientific basis and could provide a feasible method for overcome the bottleneck in the brazing diamond field.

钎焊金刚石热损伤导致高比例磨粒非正常磨损失效是当前钎焊金刚石技术领域亟待解决的瓶颈问题。在深入分析产生这一问题的根本在于现有金刚石钎焊加热方式的基础上，提出将感应加热与激光加热巧妙结合，同时采用超声振动控制焊接过程，进而实现金刚石低损伤连接的新技术。揭示感应—激光复合加热温度场耦合规律与调控机制，突破其关键实施技术，实现低损伤的金刚石磨粒牢固连接。揭示超声波振动对钎料润湿爬升金刚石、界面连接以及焊后残余应力的影响规律。进行超声波辅助感应—激光复合加热焊接金刚石的综合工艺研究，全面揭示金刚石界面连接形成机理，评价热损伤抑制情况。最后通过典型磨盘钎焊制备及其加工性能评价进行综合实验验证。本项目的完成可为彻底解决金刚石钎焊存在的瓶颈问题探索一条可行的办法，具有明确的理论和实际意义。

阐明造成当前钎焊金刚石工具应用中存在高比例磨粒非正常磨损失效这一瓶颈问题的根源在于钎焊过程的金刚石出现了热损伤，提出以构造金刚石低损伤钎焊连接温升曲线为依据，采用感应/激光复合加热实现钎焊加热，并在结合超声振动辅助实现金刚石低热损钎焊。研究了金刚石/合金界面形成机理、钎焊温度对连接界面形成及金刚石连接性能的影响，建立金刚石低热损伤连接的温升曲线构造依据。搭建感应/激光复合加热平台，揭示感应加热、激光加热的温度场分布及受工艺参数调控的变化规律。研究了复合加热下金刚石/钎料/基体界面形成机理、金刚石/钎料润湿爬升与调控、钎焊金刚石焊后残余应力及热损伤评价。解决超声辅助金刚石钎焊关键技术问题，研究了保温段和冷却段加载超声辅助的钎焊效果，揭示超声振动对钎料润湿爬升金刚石、界面连接以及焊后残余应力的影响规律。通过系列磨耗试验，系统评价了超声波辅助感应/激光复合加热焊接金刚石工艺对钎焊金刚石的热损伤抑制效果。通过典型磨盘钎焊制备及其加工性能评价进行综合实验验证。本项目为解决金刚石钎焊存在的瓶颈问题、提升钎焊金刚石工具水平提供了可靠的理论依据与支撑技术，具有很好地经济与社会效益。