摘要:残余应力发生在许多制造结构和组件中。大量的调查研究已经证明了这一现象以及其对组件力学性能的影响。残余应力对材料和构件的工程特性,特别是疲劳寿命,失真,尺寸稳定性,耐腐蚀和脆性断裂有很大的影响。因此,在实际使用条件下,残余应力分析对零件和结构构件的设计与可靠性评估是一种义务。多年来,为了获得可靠的性能,开发出了对不同组件残余应力的测定方法。过去几十年已经形成了多种具体的方法,他们的实际应用大大受益于互补技术的发展,特别是在材料的切割,全场变形测量技术,数值模拟方法和计算能力。这些互补技术的进步不仅刺激了测量的精度和可靠性增加,而且扩大了其应用范围;如今有了可用的更详细的讨论应力测量的方法。本毕业论文拟采用X射线衍射法、盲孔法等测定机体、气缸盖等机车典型铸铁件的残余应力,包括热处理前后残余应力的变化情况。通过有限元方法数值模拟典型铸铁件的残余应力,并与实际测量结果进行比对分析,通过这些研究将为最小应力浇铸及热处理工艺提供科学依据。7802
关键词:柴油机;残余应力;时效处理;数值模拟;钻孔法;X射线衍射法
Research on the diesel engine with the determination of residual stress and model
Abstract:Residual stresses occur in many manufactured structures and components. Large number of investigations have been carried out to study this phenomenon and its effect on the mechanical characteristics of these components.The engineering properties of materials and structural components, notably fatigue life, distortion, dimensional stability, corrosion resistance, and brittle fracture can be considerably influenced by residual stresses. Accordingly, residual stresses analysis is a compulsory stage in the design of parts and structural elements and in the estimation of their reliability under real service conditions.Over the years, different methods have been developed to measure residual stress for different types of components in order to obtain reliable assessment. The various specific methods have evolved over several decades and their practical applications have greatly benefited from the development of complementary technologies, notably in material cutting, full-field deformation measurement techniques, numerical methods and computing power. These complementary technologies have stimulated advances not only in measurement accuracy and reliability, but also in range of application; much greater detail in residual stresses measurement is now available.The paper by X-ray diffraction method, hole-drilling method, the locomotive body cylinder cover typical castings residual, including the changes before and after heat treatment residual stress. Typical castings residual stress by the numerical simulation of finite element method, analysis and comparison with the actual measurement results, the study will provide a scientific basis for the minimum stress of casting and heat treatment process.
Key Words: diesel engine; residual stress; aging treatment; numerical simulation; hold-drilling method; X-ray diffraction
目 录
1 绪论 1
1.1 文献综述 1
1.2 研究本课题的目的 10
1.3 研究本课题的意义 10
1.4 本课题研究的主要内容 11
1.4.1本课题研究的内容 11
1.4.2 本课题的实验方案设计 11
2 实验材料与方法 12
2.1 实验材料与设备 12
2.1.1 实验材料 12
2.1.2 实验设备 12
2.2 X射线衍射法 15
2.2.1 试样的制备 15
2.2.2 电解抛光 15
2.2.3 X射线衍射仪 16 柴油机铸铁件残余应力测定及模型建立的研究:http://www.751com.cn/cailiao/lunwen_5885.html