【摘要】：晶態(tài)Ni基釬料開始熔化溫度高、熔化溫度區(qū)間寬,釬焊時(shí)金剛石微粉易產(chǎn)生熱損傷。非晶Ni基釬料開始熔化溫度低、熔化溫度區(qū)間窄,能夠減輕金剛石微粉的熱損傷;而且,非晶Ni基釬料對金剛石潤濕能力強(qiáng),適用于短時(shí)釬焊,較短的釬焊時(shí)間可進(jìn)一步減輕金剛石微粉的熱損傷。因此,如果用非晶Ni基釬料和感應(yīng)釬焊這種短時(shí)加熱方式進(jìn)行金剛石微粉的釬焊,就可以制作出性能優(yōu)良的釬焊金剛石微粉工具。本課題以釬焊金剛石微粉磨頭的制作為例進(jìn)行了原理性論證工作,獲得了以下具有創(chuàng)新意義的結(jié)論:(1)所用非晶Ni基釬料的熱分析發(fā)現(xiàn),非晶釬料熔化溫度大約在913.8~994.2℃,相比于晶態(tài)釬料,非晶釬料熔化起始溫度降低約20℃,熔化溫度區(qū)間縮短約30℃。(2)通過釬料對金剛石和鋼基體的潤濕研究表明,在同等條件下,高溫液態(tài)釬料在180目砂紙?zhí)幚淼匿摶w上鋪展面積最大,非晶釬料對基體的潤濕強(qiáng)于晶態(tài)釬料,有利于保持釬料層的均勻性和增強(qiáng)釬料與基體的結(jié)合力;非晶釬料對金剛石的潤濕比晶態(tài)釬料好,有利于提高釬料對金剛石的把持強(qiáng)度。(3)對釬焊后的金剛石微粉磨頭理化分析表明,釬料與基體之間具有良好的冶金結(jié)合,金剛石釬焊面有Cr-C化合物生成,增強(qiáng)了釬料對金剛石磨粒的把持強(qiáng)度;非晶釬料磨頭釬料層中的金剛石微粉分布更加均勻,提高了磨頭的使用壽命。(4)磨削試驗(yàn)顯示,在同等條件下,磨削150min后,非晶釬料磨頭材料去除率是晶態(tài)釬料磨頭的3倍多,非晶釬料磨頭磨削弧區(qū)溫度比晶態(tài)釬料磨頭約低40℃;對失效磨頭再修整,非晶釬料磨頭材料去除率恢復(fù)到磨頭初始狀態(tài)的85%,而晶態(tài)釬料磨頭再修整效果不明顯。通過在釬料選用和加熱方式結(jié)合上的創(chuàng)新性嘗試,優(yōu)化了金剛石微粉的釬焊工藝,為超硬磨料釬焊工具的工業(yè)化生產(chǎn)提供了理論和試驗(yàn)依據(jù)。
[Abstract]:The melting temperature of crystalline Ni based solder is high and the melting temperature range is wide. The melting temperature of amorphous Ni based solder is low and the melting temperature range is narrow, which can reduce the thermal damage of diamond powder. Moreover, the amorphous Ni filler metal has strong wetting ability to diamond, which is suitable for short time brazing, and the shorter brazing time can further reduce the thermal damage of diamond powder. Therefore, if we use amorphous Ni solder and induction brazing to braze diamond powder, we can produce fine brazing diamond powder tool. Taking the fabrication of brazed diamond micro-powder grinding head as an example, the paper has carried on the principle demonstration work, has obtained the following innovative conclusion: (1) the thermal analysis of the amorphous Ni filler metal found, The melting temperature of amorphous solder is about 913.89994.2 鈩，

本文編號：2345875