本文選題：氬弧熔覆 + Q235鋼　； 參考：《吉林大學(xué)》2015年碩士論文

【摘要】：眾所周知，機械零部件在工程應(yīng)用中，磨損與腐蝕是其失效的主要形式。特別是隨著現(xiàn)代工業(yè)的發(fā)展，，大量工程零部件處于復(fù)雜惡劣的工作環(huán)境中，因材料表面被磨損、腐蝕導(dǎo)致的材料失效，帶來巨大的經(jīng)濟損失。為了提高性能和解決材料表面的磨損、腐蝕問題，本文以廉價的Q235鋼作為基體，利用工藝簡單靈活、成本低的氬弧熔覆技術(shù)在Q235鋼表面熔覆三種鐵基碳化物合金層，得到了具有實際應(yīng)用價值的實驗結(jié)果。 通過改變?nèi)鄹矔r的電流，通入的氣體流量，熔覆速度和預(yù)涂層厚度的大小，分析了熔覆層宏觀形貌、微觀組織結(jié)構(gòu)及顯微硬度的變化規(guī)律。獲得了本實驗條件下的最佳氬弧熔覆工藝參數(shù)，熔覆電流120A，預(yù)涂層厚度1.2mm，熔覆速度9cm/min，氬氣流量8L/min。 通過物相分析(XRD)和顯微組織觀察(SEM)，分析了熔覆層的組織形貌特點，發(fā)現(xiàn)熔覆層和母材界面處冶金結(jié)合效果良好。由界面向熔覆層方向，晶體形態(tài)由平面晶逐漸過渡到胞狀晶和樹枝晶。根據(jù)碳化物形成設(shè)計比例，在熔覆層內(nèi)發(fā)生了原位合成反應(yīng)，生成碳化物增強相。并且隨著(C-Cr-W)粉末或者(C-W)粉末添加量的增加，氬弧熔覆原位合成碳化物增強相的數(shù)量也隨之增多。 在最佳氬弧熔覆工藝條件下，熔覆層顯微硬度達到1300HV左右，大約是Q235鋼硬度的6倍；同時，氬弧熔覆后熔覆層的耐磨損和抗腐蝕性能較基體有較大提高，熔覆層最小的磨損量只有基體的1/4，磨損機制主要是磨粒磨損、粘著磨損和氧化磨損；腐蝕后的最小失重量僅有基體的1/11。在本實驗條件下，(C-Cr-W)粉末或者(C-W)粉末的比例達到70wt.%時，鎢極氬弧熔覆層各性能最佳。
[Abstract]:As we all know, wear and corrosion are the main failure forms of mechanical parts in engineering application. Especially with the development of modern industry, a large number of engineering parts are in a complex and harsh working environment. Due to the wear and corrosion of the material surface, the material becomes invalid and brings huge economic losses. In order to improve the properties and solve the wear and corrosion problems on the surface of Q235 steel, three kinds of Fe-base carbide alloy layers were cladding on the surface of Q235 steel by using simple and flexible process and low cost argon arc cladding technology. Experimental results with practical application value are obtained. By changing the current, gas flux, cladding speed and the thickness of the precoating, the changes of the microstructure, microstructure and microhardness of the cladding layer were analyzed. The optimum technological parameters of argon arc cladding under the experimental conditions are obtained, the cladding current is 120A, the thickness of precoating is 1.2 mm, the cladding speed is 9 cm / min, and the argon flow rate is 8 L / min. The microstructure and morphology of the cladding layer were analyzed by phase analysis (XRD) and microstructure observation. It was found that the metallurgical bonding effect was good at the interface between the cladding layer and the base metal. From the interface direction to the cladding direction, the crystal morphology gradually transition from plane crystal to cellular crystal and dendrite. According to the carbides formation design ratio, the in-situ synthesis reaction took place in the cladding layer to form carbide reinforcing phase. With the increase of the amount of C-Cr-W- or C-W powder, the number of in-situ synthesized carbide enhancement phases by argon arc cladding also increases. Under the optimum argon arc cladding condition, the microhardness of the cladding layer is about 1300HV, which is about 6 times of that of Q235 steel, and the wear resistance and corrosion resistance of the cladding layer after argon arc cladding are much higher than that of the substrate. The wear mechanism of the coating is mainly abrasive wear, adhesion wear and oxidation wear, and the minimum weight loss after corrosion is only 1 / 11 of the matrix. When the ratio of C-Cr-W- or C-W powder is 70 wt.%, the properties of TIG arc cladding coating are the best.
【學(xué)位授予單位】：吉林大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：TG174.4

【參考文獻】

相關(guān)期刊論文 前10條

1 劉永長,薛玉芳,宋廣生,楊根倉,周堯和;激光熔覆技術(shù)的研究現(xiàn)狀[J];粉末冶金技術(shù);1998年03期

2 劉喜明,連建設(shè),趙宇;氬弧熔覆層的強化和耐磨性[J];機械工程材料;2000年03期

3 孫榮祿;楊賢金;;激光熔覆TiC陶瓷涂層的組織和摩擦磨損性能研究[J];光學(xué)技術(shù);2006年02期

4 張勇;綦秀玲;;焊條電弧堆焊自熔性合金復(fù)合粉末的研究[J];焊接;2008年12期

5 劉自龍;王娜;斯松華;賀文文;蘇世宇;;Cr_3C_2對激光熔覆Ni基合金涂層組織與性能的影響[J];安徽工業(yè)大學(xué)學(xué)報(自然科學(xué)版);2011年04期

6 何宜柱;盧云;;激光熔覆原位合成Co_p/Cu復(fù)合涂層[J];焊接學(xué)報;2008年03期

7 李國華,丁鋼,王捧柱,曲敬信;激光熔覆鎳基合金涂層及其應(yīng)用研究[J];金屬熱處理;1999年09期

8 王振廷;陳麗麗;;氬弧熔覆WC+Ni_3Si/Ni基復(fù)合涂層的組織與耐磨性[J];金屬熱處理;2008年10期

9 劉元富;韓建民;徐向陽;李榮華;李衛(wèi)京;;等離子熔敷Cr_7C_3金屬陶瓷增強復(fù)合涂層組織與耐磨性研究[J];摩擦學(xué)學(xué)報;2006年03期

10 李剛;劉政;張娜;;熔覆速度對氬弧熔覆鐵基合金涂層組織及性能的影響[J];徐州工程學(xué)院學(xué)報(自然科學(xué)版);2009年02期

相關(guān)博士學(xué)位論文 前1條

1 宗琳;原位自生陶瓷復(fù)合堆焊層的組織與耐磨性研究[D];沈陽工業(yè)大學(xué);2012年

本文編號：1810879