不同热处理对牙科银钯铸造合金显微硬度的影响

Influence of cryogenic treatment and age -hardening he at treatment on the microhardness of palladium silver dental alloys

目的探讨不同热处理对牙科银钯铸造合金显微硬度的影响。方法自制牙科银钯铸造合金,用牙科标准铸造程序制作合金试件。试件加热到900℃后冰水中淬火作软化热处理,然后分组分别进行硬化热处理、深冷处理、硬化热处理并深冷处理,以软化热处理组作为对照组。测试经不同热处理后合金的显微硬度,进行统计学分析。结果与对照组相比,硬化热处理、深冷处理、硬化热处理并深冷处理均提高了合金的显微硬度,硬化热处理组提高了129%,深冷处理组提高了13%,硬化热处理并深冷处理组提高了141%。结论硬化热处理和深冷处理均可以提高合金的显微硬度,而硬化热处理的提高更为明显;当硬化热处理和深冷处理联合应用时,二者对合金硬度的提高可产生累加效应。

Objective The purpose of this study was to investigate the influence of cryogenic treatment and age- hardening heat treatment on the micro-Vieker＇s hardness of palladium-silver dental alloys. Methods A low-gold content dental casting alloy composed of Ag-Pd-Cu-Au was prepared for this study. Experimental specimens according to standard requirements were prepared following a standard dental laboratory casting procedure, cast specimens were heated to 900 ~C and quenched in ice water. The specimens were then divided into 4 groups. They were subsequently subjected to different treatments, including age-hardening heat treatment, cryogenic treatment, heat treatment combined with cryogenic treatment. The non-treated group was used as control The micro-Vicker＇s hardness value was examined. The significance of correlation was analyzed. Results The miero-Vicker＇s hardness of specimens after age-hardening heat treatment, cryogenic treatment, heat treatment combined with cryogenic treatment increased by 129%, 13% and 141%, respectively, compared with that of the non-treated control group. Conclusion Age-hardening heat treatment and cryogenic treatment were effective in elevating the hardness of Ag-Pd-Cu-Au alloy.