Ni对金刚石磨具陶瓷结合剂性能的影响

采用粉末冶金法制备了不同Ni含量的金刚石磨具陶瓷结合剂。通过SEM、EDS、XRD、TG-DSC、三点弯曲等分析方法对含Ni陶瓷结合剂的微观结构、结合界面、氧化性能以及抗折强度等性能进行分析,同时研究了含Ni陶瓷结合剂对金刚石润湿性的影响。结果表明,在实验范围内,Ni的加入对陶瓷结合剂耐火度及流动性影响不大,但降低了结合剂的烧成收缩;750℃烧成时,Ni与陶瓷结合剂界面结合紧密,界面形成合金化结合,提高了结合强度,抗折强度随着Ni的加入量先升高后降低,当Ni含量为15%(质量分数,下同)时达到最大值62.8MPa,较基础陶瓷结合剂提高了19.41%;Ni的加入能够改善高温状态下陶瓷结合剂对金刚石的润湿性,当Ni添加量为15%时,陶瓷结合剂对金刚石的润湿角为64°,比未添加Ni时的润湿角(84.5°)减小了24.3%。

Effect of Nickel on the Properties of Vitrified Bond for Diamond Grinding Tool

The vitrified bond mixing with different amounts of Ni(Ni/VB) was prepared by the method of powder metallurgy.The microstructure,interfaces,oxidizability and the compressive strength of the Ni/VB were analyzed by SEM,EDS,XRD,TG-DSC and three-point bending test.The wettability between the different vitrified bonds and the diamonds was also investigated.The results showed that the adding Ni had little effect on the refractoriness and the liquidity of the vitrified bond,but reducing the firing shrinkage of the vitrified bond.The interface between the vitrified bond and the Ni was closely bonding at 750℃.With adding the content of 15wt%Ni,the compressive strength of the Ni/VB got the maximum,62.8MPa,which was higher 19.41% than the non-adding Ni.It was also found that the adding Ni could give a better wettability between the vitrified bond and the diamonds at high temperatures.The wetting angle between the Ni/VB and the diamonds was 64°,which was lower 24.3% that the non-adding Ni(84.5°).