摘要当今社会，绿色发展，节能发展是两个重要的发展命题。针对现今的经济发展状 况，科学界提出了绿色再制造发展技术。而堆焊具有高效、经济、节能等优点，成为 绿色再制造技术的核心之一。采用堆焊技术对尺寸大、附加效益高以及具有特殊性能 需求的零部件进行修复或再制造，可以有效的延长这些零部件的使用年限，具有重要 的应用及经济价值。其中，使用 Fe-Cr-C 基材料作为堆焊合金时，由于其组织中含有 大量的 M7C3 型碳化物，能有效地提高堆焊合金的耐磨性。但是因为 M7C3 型碳化物 较为粗大，在服役期间，碳化物易大量地剥落，导致严重限制了对基体耐磨性的改善 能力。81344

本试验采用本课题组自制的无渣自保护药芯焊丝在试板上进行堆焊试验。为了研 究钒对堆焊合金的耐磨性及微观组织的影响，通过在药芯焊丝上分别加上质量分数不 同的钒，研究了 M7C3 型碳化物在微观组织下的形貌与数量，并分析了由组织的变化 而引起的硬度和耐磨性的改变的原因。即随着钒含量的增加，碳化物的形貌呈不规则 形态，细化了基体组织，从而提高了堆焊合金的硬度和耐磨性。但是，在焊丝中加入 含量超过 18%的钒铁时，堆焊出的合金性能不再提高。所以本试验中，加入 18%钒 铁的合金性能最优异。

毕业论文关键词：钒；堆焊合金；耐磨性；微观组织

Abstract In today's society, green development, the development of energy conservation and development are the two important propositions。 According to the present economic development, scientific development of green remanufacturing technology are put forward。 The surfacing has the advantages of high efficiency, economy, energy saving, become one of the core of the green remanufacturing technology。 By surfacing welding technology of large size, high additional benefits as well as with special performance requirements of spare parts for repair or remanufacturing, can effectively extend the use of these parts fixed number of year, have important application and economic value。 Among them, using Fe-Cr-C base material as a surfacing welding alloy, because of its organization type contains a large number of M7C3 carbide, can effectively improve the wear resistance of surfacing welding alloy。 But because type M7C3 carbide relatively bulky, during the period of service, carbide heavily flake easily, cause serious restricts to improve the ability of matrix wear resistance。

This experiment adopts the physical homemade without slag self-protection flux cored wire welding experiment was carried out on test plate, in order to study the wear resistance and microstructure of vanadium of surfacing welding alloy and the effect of on the flux-cored wire respectively with different mass fraction of vanadium, studies the type M7C3 carbide in the microstructure morphology and quantity, and analyzed the change caused by the organization's reasons for the changes of hardness and wear resistance。 With the increase of the content of vanadium carbide morphology of irregular form, refine the matrix organization, so as to improve the hardness and wear resistance of  surfacing welding alloy。 However, in the add content more than 18% of vanadium iron wire, welding alloy performance doesn't increase。 So in this experiment, add 18% vanadium iron alloy performance is the most outstanding。

Keywords：Vanadium；Hardfacing；Wear Resistance；Microstructure

目 录

第一章 绪论 1

1。1 选题背景及意义 1

1。2 堆焊技术及其发展 2

1。3 堆焊合金的磨损机制 3

1。3。1 微观切削磨损