钎焊单层金刚石砂轮的现存问题及其对策

Difficult Problems and Its Countermeasures of Brazed Bonded Monolayer Diamond Grinding Wheel

关键词:  砂轮  钎焊  单层  金刚石磨料

Key words:  grinding wheel  brazing  monolayer  diamond grit

摘要:

概述了用活性钎料将金刚石磨料钎焊到钢基体表面制作单层金刚石砂轮,比传统的单层电镀金刚石砂轮具有明显的工艺优势。分析指出了钎焊工艺的现存问题,即如何实现金刚石磨料与合金钎料层高的结合强度、钎料层厚度的均匀性和金刚石磨料的有序排布。给出了可行的解决方案,即利用Ag-Cu-Cr或Ni-Cr等活性钎料与金刚石界面化学反应生成的Cr₇C₃和Cr₂₃C₇实现钎料层与金刚石间的高强度结合;通过砂轮地貌优化,优化出磨粒排布方式,然后按优化的结果排布磨料。研制出了具有磨料出露高度高、有序排布、钎料层厚度一致性、高结合强度、高锋利度的单层钎焊金刚石砂轮。

Abstract:

Monolayer diamond grinding wheel Manufactured by brazing diamond grit to steel substrate of grinding wheel with active brazing filler mental has distinct advantages over traditional electroplated monolayer diamond grinding wheel.The paper pointed out the existing technical difficult problems,which are how to increase bond strength,how to improve the uniform of the brazing layer thickness,and how to realize regular distribution of diamond grit.Some countermeasures to solve them are discussed.Firstly,Ni-Cr or Ag-Cu-Cr alloy was used as an active filler mental for brazing diamond grit,which can provide high bond strengththrough Cr₇C₃ and Cr₂₃C₇ produced by interaction between Cr atom of Ni-Cr or Ag-Cu-Cr alloy and C stom of diamond surface at elevated temperature.Secondly,regular grits were distributed in accordance with optimized topography.On the analyses,a diamond grit wheel with high bond strength,regular grit distribution and uniform layer thickness of the brazed alloy was developed.