濺鍍於D2鋼上氮化鋯鍍層之機械性質研究

Mechanical Properties of Thick ZrN Coatings on D2 Steel Deposited by Unbalanced Magnetron Sputtering

張閎皓(Chang, Hung Hao)

指導教授 ： 喻冀平 ； 黃嘉宏

國立清華大學/原子科學院/工程與系統科學系/碩士(2015年)

https://doi.org/10.6843/NTHU.2015.00161

摘要

本研究的目的為在D2工具鋼上鍍製氮化鋯厚膜，並研究厚膜之結構與機械性質隨著厚度的變化。實驗中控制的製程參數為鍍膜腔體和渦輪分子幫浦之間閘閥的開口大小，以及鍍膜的時間長短，而鍍膜腔體內氣體的抽氣速率隨著閘閥開口大小而改變。實驗中採用兩組製程參數，分別為全開閥及半開閥。實驗結果顯示膜厚超過6微米的氮化鋯厚膜成功被鍍製在D2工具鋼基材上。所有試片的硬度介於26.0-27.7GPa之間，並且不隨膜厚而改變。半開閥系列具有較高的附著性以及耐磨耗性，這可能歸因於半開閥製程中較高的氣體離化率造成排列較佳的厚膜結構，並且有助於鍍膜過程中厚膜內的應力釋放。然而，在兩種鍍膜製程中皆發生了靶材毒化現象，並且導致電弧產生的微粒埋入厚膜中。在厚膜內接近基材的部分受到微粒的影響較少，結構較為緊密。反之，埋入厚膜中的微粒造成遠離基材的上層區域形成孔洞並且結構較為鬆散。由於厚度較大的試片內部結構鬆散的部分較多，因此試片內的殘餘應力隨著厚度上升而減小。並且，由於結構鬆散的區域對磨耗的抵抗能力較差，因此ZrN厚膜的磨耗率隨著厚度上升而增加。本實驗採用的兩種製程方式相較之下，半開閥製程能以較快的鍍膜速率，並且在較低的渦輪分子幫浦消耗能量以及工作溫度下鍍製出高品質的ZrN厚膜，因此較為貼近工業應用的需求。

關鍵字

鍍層 ； 氮化鋯 ； 厚膜 ； 附著性 ； 磨耗

並列摘要

The objective of this study was to deposit thick ZrN coatings on AISI D2 steel substrates, and to investigate the structure and properties of the ZrN coatings with varying thickness. The controlling deposition parameters were the opening level of the gate valve between the deposition chamber and the turbomolecular pump (TP), and the deposition duration. The pumping speed of the gas inside the deposition chamber was changed with the different opening level of gate valve. Two deposition conditions were adopted, which were the full opening of gate valve (FV) and half opening of gate valve (HV) conditions. The results showed that ZrN coatings with thickness over 6μm were successfully deposited on the D2 steel substrates. The hardness of the ZrN coatings was ranged from 26.0 to 27.7 GPa without significant variation with thickness. The HV-series possessed higher adhesion strength and wear resistance. This could be due to the higher gas ionization rate in HV-condition, which promoted the stress relief during deposition and leaded to better-arranged structure. However, target poisoning occurred in both deposition conditions and the macro-particles generated from arcing were buried into the coatings. The region near the substrate was less affected by the particles and therefore denser . By contrast, the buried particles resulted in the internal voids and loose packed structure in the upper region of coatings which is away from the substrate. Due to larger portion of loose packed region in the thicker coatings, the residual stress of the ZrN coatings was decreased with increasing thickness. Furthermore, the loose packed region was less resistant to wear, leading to the increasing wear rate with thickness. In comparison of the two deposition conditions, ZrN coatings with higher quality could be produced by HV-condition with higher deposition rate, lower energy cost and lower working temperature of TP, indicating that HV-condition was more suitable for industrial application.

並列關鍵字

Coating ； ZrN ； Thick coating ； Adhesion ； Wear

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