(1. 蘭州理工大學(xué) 有色金屬先進(jìn)加工與再利用國家重點(diǎn)實(shí)驗(yàn)室，蘭州 730050；
2. 金川集團(tuán)機(jī)械制造有限公司，金昌 737102)
摘 要: 采用等離子噴焊技術(shù)在d100 mm×30 mm 45號鋼圓柱基體上制備厚度為5 mm的高鋁青銅噴焊層，將制備的噴焊工件在距基體底部分別為32、33和34 mm處進(jìn)行水平切割，切割后留在基體上的噴焊層厚度分別為2、3和4 mm。在室溫條件下，研究噴焊層中元素?cái)U(kuò)散對其組織、硬度和摩擦磨損性能的影響。結(jié)果表明：隨分隔層位置從基體到噴焊層縱深方向距離的增加，F(xiàn)e元素?cái)U(kuò)散作用減弱；靠近基體的噴焊層中Fe元素含量較多，富Fe 的k相含量多，且呈點(diǎn)狀或球狀團(tuán)聚在一起，噴焊層與鐵基對摩件的組織相容性增加，在摩擦過程試樣易與對摩件黏著；噴焊層硬度雖高，但磨損率較高；靠近噴焊層表面的噴焊層中Fe元素含量最低，k相相貌由粗大樹枝狀向細(xì)小樹枝狀和粒狀組織轉(zhuǎn)變，摩擦因數(shù)和磨損率均有所降低, 黏著磨損受到抑制，主要磨損機(jī)理為磨粒磨損。
關(guān)鍵字: 等離子噴焊層；元素?cái)U(kuò)散；k相形貌；摩擦；磨損
（1. State Key Laboratory of Advanced Nonferrous Materials Process and Recycles,
Lanzhou University of Technology, Lanzhou 730050, China;
2. Jinchuan Machinery Manufacturing Co., Ltd., Jinchang 737102, China）
Abstract:High-aluminum bronze coating with a thickness of 5 mm was sprayed by plasma spray welding on 45 medium carbon steel with size of d100 mm×30 mm. The workpieces were cut at zones of 32, 33, and 34 mm from the bottom of the substrate. The thicknesses of coatings on the substrate were 2, 3 and 4 mm, respectively. The effects of element diffusion on the phase structure, microhardness, friction and wear behavior were analyzed at room temperature. The results show that Fe element coming from substrate diffuses into the coating. With increasing the distance from the interface, Fe element diffusion decreases. The volume fraction of Fe-rich k phase is relatively high on the sprayed layer near the substrate. This increases the compatibility of structure between the coating and Fe-based counterpart. The k phase of coating gathers into spots or globules. Such k phase tends to stick the counterpart during friction process, which even causes some particles. Therefore, its wear behavior is the worst despite of the high hardness of coating. However, in the sample near the surface of coating, the bulky dendritic k phases change to small dendritic and granular ones, and thus results in a decrease of adhesive wear, which causes a low friction coefficient and wear rate. The wear mechanism is characterized as abrasive wear.
Key words: plasma spray coating; element diffusion; phase morphology; friction; wear
