碳化鎢顆粒之間由於結合性不佳，經過人們研究發現，可以將鈷熔融後有效地與碳化鎢相互連接，形成金屬與陶瓷的複合材料。最廣泛應用的鎢鋼圓棒刀具產品是含有10%鈷含量的材質，因為兼具足夠的硬度及韌性，適合被開發出需要耐磨耗、耐衝擊且不易脆斷的工具，在工業發展上扮演重要的角色，也正因為與工業發展關係密切，在這個進步速度爆炸的年代，舊有的10%鈷含量鎢鋼圓棒刀具材質已經無法滿足所有工作環境的需求，因此人們隨著工作條件需求傾向，調整鎢鋼產品的機械性質，進一步將工業發產推向更高的水平。
在品質提升方面，最直觀的方式除了改變碳化鎢的晶粒大小以外，許多學者或鎢鋼產品製造商也從調整碳化鎢與鈷的比例方面著手，歸納出碳化鎢晶粒越細則產品硬度越高；鈷含量越高則產品韌性越佳的趨勢，然而，一般認為硬度的提升會導致韌性降低，若只改變晶粒大小或調整鈷含量的不同，將難以得到兼具高硬度與高韌性的產品。
再更深入探討影響機械性質的因素後，發現鎢鋼產品的碳含量的確佔有舉足輕重的地位，碳含量過高、過低都會導致缺陷且使產品壽命降低。鎢鋼產品常被使用於高危險的作業環境，品質不佳必然產生使用者的安全上的疑慮並且不利於機台使用的穩定，同時帶給生產者及使用者雙方的不便。因此，在生產鎢鋼的過程中必須加入碳含量控制的因素，目的是為了將碳含量穩定在適當的範圍內。
本篇論文是由台灣科技大學與春保森拉天時進行產學合作計畫，致力於研究探究鎢鋼中碳化鉻與碳化釩的添加對鎢鋼機械性質與微結構的影響。為了再更精進鎢鋼的品質及開拓其使用範圍，參雜其他元素的理念提供給鎢鋼產業更上一層台階的機會，因此，許多碳化物，例如：碳化鈦、碳化鉻、碳化鉭、碳化釩等等，被嘗試著添加到碳化鎢與鈷的組合之中，人們利用不同元素彼此之間的相互作用，研究並找出是否能突破原有的極限，加上經驗、時間以及製程方面的累積，做出一步步的改善，鎢鋼產業將持續進化。

Tungsten carbide particles are difficult to joint to each other if there are no intermedia in between. Researchers have found that cobalt’s liquid phase has ability to reinforce the microstructure of tungsten carbide. Thereby, the most widely used tungsten carbide rods usually contain 10wt% of cobalt. This composition has characteristic of high wear-resistance, high impact strength, and high tolerance of chipping because the amount of cobalt provides sufficient toughness and tungsten carbide grains maintain the hardness. Tungsten carbide plays an important role in terms of industrial development. However, commonly used solid tool blanks with 10wt% cobalt is not suitable for all kinds of tasks, since end user’s working environment is becoming more and more difficult with rising industrial requirements, especially in the aerospace industry. Therefore, researchers tend to satisfy the working condition by means of promoting mechanical properties which are governed obviously by grains size of tungsten carbide and the proportion of cobalt.
Generally, tungsten carbide’s toughness and hardness are inversely proportional to each other if we merely alter those two parameters mentioned above. According to articles, carbon content indeed influences mechanical properties a lot due to percentages of carburization and wetting angle during sintering process. Therefore, carbon balance control is a crucial factor all over the processes. Wear resistance would greatly reduce if carbon content is over the limit, while insufficiency in carbon content will lead to brittleness and shorten tool’s life time. Tungsten carbide products are often used in the environment with high risks. If the quality is not stable, it is impossible to ensure the security to user and even harmful for the machines where the products being installed in.
Through the cooperation of National Taiwan University of Science and Technology(NTUST) and CB-CERATIZIT group(CBCT), experiments have been conducted mainly on the influences of mechanical properties and microstructure of tungsten carbide after doping with varied amount of cubic carbide, such as chromium carbide and vanadium carbide. In order to achieve further improvements, other researchers have started to dope different kinds of carbides, such as titanium carbide, chromium carbide, tantalum carbide, vanadium carbide, etc. Taking the advantage of chemical interaction between those carbides and tungsten carbide or cobalt, people have been trying to enhance mechanical properties of tungsten carbide and pushing the boundary in various applications.

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