多重表面處理對AISI H13工具鋼熱熔損及耐磨耗性質之影響

The Effects of Thermal Erosion and Wear Resistance on AISI H13 Tool Steel by Multiple Surface Treatments

王永祥(Yung-Hsiang wang)

指導教授 ： 張世賢

國立臺北科技大學/工程學院/材料科學與工程研究所/碩士(2010年)

https://doi.org/10.6841/NTUT.2010.00048

摘要

本實驗是利用不同的表面處理及其組合，來改善一般壓鑄用模具材料的使用壽命，主要比較無處理、氮氧化、CrN鍍層以及氮氧化後再披覆CrN鍍層處理等之試片，對於A380鋁合金的抗熱熔損以及耐磨耗性質測試。經由三小時的熔損實驗後，可以發現氮氧化後再披覆CrN鍍層的多重表面處理，其重量損失是最少的，僅有0.8 %的重量損失，與未處理試片的3.2 %相比，明顯地改善了75 %的重量損失，而其它的表面處理也都有延緩A380鋁合金熔損行為的效果。
隨著熔損時間的增加，會發現在試片表面所產生的鐵鋁矽化合物有增厚的現象，從CrN鍍層處理的試片經過熔損三小時後的金相組織可以看出，A380鋁合金的侵蝕方式是由部分的點開始破壞，當開始與鐵產生擴散作用後，產生鐵鋁矽化合物層，進而被鋁湯所侵蝕。
在磨耗測試中，所有經由表面處理後的試片皆展現出較好的耐磨耗性質，而未處理試片有非常明顯的磨耗痕跡出現，然而，氮氧化、CrN鍍層、氮氧化加CrN鍍層試片只有很淺的磨耗痕跡，可知經由表面處理後確實可以提升AISI H13工具鋼試片的磨耗性質。經由氮氧化後披覆CrN的多重表面處理試片，具有最低的摩擦係數，平均值大略為0.28左右。

關鍵字

氮氧化 ； CrN ； A380鋁合金 ； 熱熔損 ； 磨耗 ； AISI H13 tool steel

並列摘要

The experiment is used of different surface treatments and combinations, then to evaluate and improve the tool life of die casting materials. This research compares of erosion and wear resisatnce of A380 alloy via different surface treatment of untreated, oxynitriding, CrN coating, and CrN coated with oxynitriding specimens. The minimun melt loss was appeared in multiple surface treatments of CrN coated with oxynitriding after 3 hours eoosion test. It showed that only has 0.8% of weight lost, however the untreated specimen was 3.2%. The experimental results was obviously improved 75% of the weight loss, meanwhile the other surface treatment also has a lower erosion rate of A380 aluminum alloy.
Increasing of the soaking time of melting aluminum alloy, the thinkness of Fe-Al-Si compounds was increased after erosion tests. The optical microstructure showed that the erosion mechanism of CrN coating specimens by A380 alloy which was beginning damage from the point of surface after 3 hours test. When the aluminium alloy is beggining to diffusion with iron elements, it will result in the Fe-Al-Si compound layer, which was quickly eroded by melting aluminum solution.
All theses specimens of different surface treatment were showed the better wear- resistances after wear tests. Furhtermore the untreated specimen shows a very obviously trace of wear appear. However, there was very shallow of wear traces specimens of oxynitriding, CrN coating, and CrN coated with oxynitriding treatment. It shows the wear properties of AISI H13 tool steel can be enhanced by different surface treatment. In attition, the lowest frictional coefficient of H13 specimen was appeared in multiple surface treatments of CrN coated with oxynitriding. The average value of frictional coefficient is about 0.28.

並列關鍵字

Oxynitriding ； CrN coating ； A380 alloy ； erosion ； wear ； AISI H13 tool steel

參考文獻

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