利用高速火焰熔射技術製作鎳基自熔合金耐磨耗塗層之研究

Study on Wear Resistance of Ni-based Self-Fluxing Alloy Sprayed by HVOF

黃德宜(Te-Yi Huang)

指導教授 ： 蘇程裕

國立臺北科技大學/機電學院/機電整合研究所/碩士(2008年)

摘要

本文以四種顆粒大小與WC添加多寡的商業用鎳基自熔合金粉末為基礎，經熔射後，以一大氣壓氮氣保護的條件對各塗層進行重熔處理，重熔溫度分別為950°C、1000°C與1050°C。為探討塗層經重熔後，晶粒組織與相態變化，並且找出塗層磨耗機制，從而找出最適合用在磨耗上的塗層，對各塗層進行各種物性分析、微硬度分析與磨耗試驗。
試驗結果顯示，經950°C重熔後，各塗層會趨向緻密，此時塗層的硬度與磨耗性質為相對最佳；相態變化方面，塗層在950°C時，Cr會析出，與C、B形成硬化相，Ni也與B形成硬化相，同時未熔融的Ni形成固溶體，隨著重熔溫度提高，晶粒會出現粗大化現象，造成孔洞增加，硬度下降；磨耗方面，各塗層經950°C重熔後，皆較未重熔時硬度下降，但抗磨耗性質卻較佳，添加WC的塗層其磨耗性會較佳，磨耗機制則以磨損、黏著與表面疲勞為主。
四種塗層中以TSM2002塗層經950°C重熔後為最佳，能得到一硬度超過700Hv、孔隙率低於1%，抗磨耗性佳的塗層。

關鍵字

熔射 ； HVOF ； 自熔合金 ； 磨耗

並列摘要

This study focuses on the effects of the reflowing process on the physical properties、hardness analysis and wear test by four Ni-based self-fluxing alloy powders with different particle size mixed WC-Co powder by different weight ratio under reflowing temperature 950°C、1000°C and 1050°C by nitrogen in atmospheric pressure after thermal spray.
The results show that the dense coatings can be prepared and also exhibit good hardness and wear performance at reflowing temperature of 950℃. On the phase change, chromium increases the hardness of the coatings by the formation of hard phase with carbon and boron, nickel react with boron into a hard phase and the others change into Ni-solution. According to the elevated temperature, the hardness is decreased but the porosity is increasing because of the grain growth. On the wear resistance, each coating has worse hardness and better wears resistance, especially the coating adding WC-Co. The major wear mechanisms are based on abrasive wear、adhesive wear and surface fatigue. The TSM2002 coating after 950°C reflowing has the hardness which his more than 700Hv and exhibits the porosity under 1% which is the best coating with wearability among these four coatings.

並列關鍵字

Thermal Spray ； HVOF ； Self-Fluxing Alloy ； Wear

參考文獻

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