激光再制造镍基高温合金工艺及其高温拉伸性能的研究

发布时间：2018-02-25 16:20

本文关键词： 激光再制造镍基高温合金工艺优化组织高温性能　出处：《南京航空航天大学》2016年硕士论文　论文类型：学位论文

【摘要】：在国家提倡资源可持续发展的要求下,再制造工程应运而生,该工程本着优质、高效、环保、节能、节材的准则,节约了大量的成本,提高了资源的利用率。激光再制造技术是基于再制造工程与激光快速成形技术发展起来的一种先进再制造技术,该技术在航空航天、大型机械设备、化工石油等领域的再制造工作中已得到广泛应用。本文将激光再制造技术运用到航空材料的再制造中。主要从机理分析、再制造工艺选择、再制造件的性能测试等方面对航空发动机高压压气机叶片常用材料GH4169镍基高温合金的再制造工作进行了研究分析,具体研究内容如下:(1)研究了激光再制造技术的相关机理,包括材料与激光的相互作用机理、熔池内部对流形成分析、熔池内形核及晶核长大过程分析。(2)基于曲面响应法研究了激光功率、扫描速度对单道熔覆层形貌特征的影响,基于稀释率与接触角这两个指标对工艺参数带进行了优化,并最终得到7组优化参数。(3)采用优化后的7组工艺参数进行了再制造试验,通过选择合适的扫描路径、搭接率对失效件进行再制造。研究激光功率、扫描速度对修复区微观组织的影响,并对修复区内析出相进行分析研究。(4)对再制造件的高温力学性能进行了研究分析,根据零件在工作中的受力情况,重点对再制造件的高温拉伸性能进行了研究。从抗拉强度、屈服强度、断后延伸率、断面形貌等方面分析了7组再制造件,其中1号再制造件修复效果最好,屈服强度已超过无损件的4.3%,从零件正常使用角度来看,再制造件的高温拉伸性能已经超过了无损件,达到了再制造的目的。
[Abstract]:Under the request of the country to promote the sustainable development of resources, the remanufacturing project has emerged as the times require. The project is based on the principles of high quality, high efficiency, environmental protection, energy saving and material saving, and saves a lot of costs. Laser remanufacturing technology is an advanced remanufacturing technology based on remanufacturing engineering and laser rapid prototyping technology, which is used in aerospace, large mechanical equipment, The laser remanufacturing technology has been widely used in the fields of chemical and petroleum industry. In this paper, the laser remanufacturing technology is applied to the remanufacturing of aeronautical materials. The remanufacturing work of GH4169 nickel-base superalloy, a common material for aeroengine high-pressure compressor blade, is studied and analyzed in aspects of performance test of remanufacturing parts. The specific research contents are as follows: (1) the related mechanism of laser remanufacturing technology is studied. Including the interaction mechanism between material and laser, the analysis of convection formation in the molten pool, the analysis of nucleation and nucleation growth process in the molten pool. (2) based on the surface response method, the effects of laser power and scanning speed on the morphology of the single pass cladding layer are studied. The process parameters were optimized based on dilution rate and contact angle, and 7 groups of optimized parameters were obtained. The influence of laser power and scanning speed on the microstructure of the repair zone was studied. The precipitation phase in the repair zone was analyzed and the mechanical properties of the remanufactured parts at high temperature were studied. According to the stress of the parts at work, the high temperature tensile properties of the remanufactured parts are studied. Seven groups of remanufactured parts are analyzed from the aspects of tensile strength, yield strength, elongation at break, section morphology, etc. The No. 1 remanufactured part has the best repair effect and the yield strength is higher than that of the non-destructive part. From the point of view of the normal use of the parts, the high temperature tensile properties of the remanufactured parts are better than the non-destructive parts, and the purpose of remanufacture is achieved.
【学位授予单位】：南京航空航天大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TG665;V252

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