碳工具鋼超深冷處理後耐磨性研究

Improving Wear Resistance of CarbonTool Steel by Cryogenic Treatment

楊銘文(Meng-Wen Yang)

指導教授 ： 陳永傳

國立臺灣大學/工學院/機械工程學研究所/碩士(2006年)

https://doi.org/10.6342/NTU.2006.01394

摘要

本實驗以超深冷處理的方式進行碳工具鋼的安定化處理，將淬火、回火後的試片，進一步緩慢冷卻至-196℃的低溫，保持適當時間，促使其微細碳化物析出，內應力釋放，組織結構完全安定化，而達到提升耐磨性與韌性的目標。
本文的主要目的在研究超深冷處理條件(降溫速率、持溫時間、升溫速率等)對碳工具鋼之耐磨性及韌性的影響。實驗結果顯示:

1.當碳工具鋼欲利用超深冷處理改善韌性時，其本身必須先具備一定程度的韌性，否則就算經過超深冷處理後，韌性亦無法獲得有效改善。
2.經過淬火、回火後的碳鋼具鋼再施以超深冷處理，其硬度值依舊幾乎不變。
3.將淬火、回火後的碳工具鋼實施超深冷處理後，其耐磨性有相當顯著的提升。
4.淬火、回火後的碳工具鋼以較緩慢的降溫速率實施超深冷處理對其耐磨性的改善效果較大。
5.超深冷處理對於磨料磨耗及黏著磨耗，有明顯的抵抗效果。
6.經過淬火、回火後的碳鋼具鋼，實施超深冷處理時，若冷速太快可能造成內應力，而使碳工具鋼有斷裂之虞，因此冷速太快的超深冷處理不宜使用。

關鍵字:超深冷處理,韌性耐,磨性

關鍵字

超深冷處理 ； 韌性 ； 耐磨性

並列摘要

The present experiment utilizes cryogenic treatment to stabilize the microstructure of tool steel. Let the workpiece which has been quenched and tempered cooling down to -196℃ and holding proper times to pre-
cipitate tiny carbides, release internal stress, stabilize the microstructure completely, and to reach the target of improving wear resistance and toughness.
The purpose of the present experiment is to investigate the influence of cryogenic treatment condition (cooling rate, keeping time, and rasing rate) on the wear risistance and toughness of carbon tool steel. The results obtained are as follows:
1. Carbon tool steel, must possess medium level of toughness itself, otherwise its toughness is unable to be improved even after a cryogenic treatment.
2. The hardness of carbon tool steel which has been quenched and tempered still keeps unchanged after a cryogenic treatment.

3. Cryogenic treatment can enhance the wear resistance of quenched - tempered carbon tool steel effectively.
4. The wear resistnace of carbon tool steel can be improved more signific- antly by using a slower cooling rate in cryogenic treatment.
5. Carbon tool steel can get significant resistance for abrasive wear and adhesive wear after cryogenic treatment.
6. During cryogenic treatment thermal stress may be induced if the cooling rate is too fast; hence the cryogenic treatment with fast cooling rate can not to be used.

Keywords: Cryogenic treatment, Toughness, Wear resistance.

並列關鍵字

Cryogenic treatment ； Toughness ； Wear resistance.

參考文獻

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