本文選題：高應(yīng)力氣門彈簧 + 疲勞斷裂��； 參考：《機(jī)械科學(xué)研究總院》2012年碩士論文

【摘要】：彈簧是各類機(jī)械設(shè)備、裝置的重要零部件。近年來，隨著主機(jī)對(duì)彈簧性能要求的提高，高應(yīng)力彈簧隨之出現(xiàn)。通常高應(yīng)力彈簧是指服役應(yīng)力大于800MPa的彈簧，其主要應(yīng)用領(lǐng)域和產(chǎn)品是：汽車用高應(yīng)力彈簧、高速機(jī)車用高應(yīng)力彈性元件、大型工程機(jī)減震及緩沖彈簧、電力裝備及管路系統(tǒng)平衡彈簧、閥門用彈簧等。 高應(yīng)力氣門彈簧是國家中長期科技發(fā)展規(guī)劃綱要中重要的基礎(chǔ)零部件，其質(zhì)量的優(yōu)劣直接影響著主機(jī)的性能和安全。隨著我國經(jīng)濟(jì)技術(shù)的迅猛發(fā)展，主機(jī)對(duì)高應(yīng)力氣門彈簧輕量化、高可靠性、高疲勞壽命等要求越來越高。 高應(yīng)力氣門彈簧具有設(shè)計(jì)承載應(yīng)力大、應(yīng)力幅變化大、更換困難、工作環(huán)境復(fù)雜及高疲勞壽命要求和抗松弛性能要求高等特點(diǎn)。其中高的疲勞壽命和高抗松弛性能要求是各項(xiàng)要求中最為核心的要求，只有保證高的疲勞壽命和抗松弛性才能滿足主機(jī)在壽命期內(nèi)的正常運(yùn)行。 隨著高應(yīng)力氣門彈簧設(shè)計(jì)制造水平的進(jìn)一步提高，，其疲勞性能、抗松弛性能要求越來越引起人們的關(guān)注，所以本文著重對(duì)高應(yīng)力氣門彈簧可靠性分析進(jìn)行研究。 基于以上分析，本文采用了基于疲勞斷裂的高應(yīng)力氣門彈簧疲勞可靠性分析和基于負(fù)荷衰減的高應(yīng)力氣門彈簧疲勞可靠性分析兩種方法對(duì)高應(yīng)力氣門彈簧進(jìn)行疲勞可靠性分析。重點(diǎn)開展了以下幾方面的研究工作： （1）結(jié)合彈簧內(nèi)部殘余應(yīng)力分析，系統(tǒng)研究了高應(yīng)力氣門彈簧疲勞強(qiáng)度和疲勞壽命的特點(diǎn)，并給出了影響高應(yīng)力氣門彈簧疲勞性能的關(guān)鍵因素； （2）在高應(yīng)力氣門彈簧疲勞強(qiáng)度分析的基礎(chǔ)上，重點(diǎn)研究了噴丸強(qiáng)化工藝提高高應(yīng)力氣門彈簧疲勞性能的強(qiáng)化原理；結(jié)合相關(guān)理論分析對(duì)噴丸強(qiáng)化兩種強(qiáng)化機(jī)制進(jìn)行了試驗(yàn)驗(yàn)證； （3）分析了高應(yīng)力氣門彈簧高疲勞可靠性要求的原因，重點(diǎn)討論了高應(yīng)力氣門彈簧疲勞失效的兩種判據(jù)，并給出了高應(yīng)力氣門彈簧疲勞可靠性分析的流程； （4）在傳統(tǒng)疲勞斷裂壽命的前提下，研究了基于三參數(shù)威布爾分布的高應(yīng)力氣門彈簧P-S-N曲線的數(shù)學(xué)模型和擬合方法；在此基礎(chǔ)上研究了基于三參數(shù)威布爾分布的高應(yīng)力氣門彈簧疲勞剩余壽命的可靠性數(shù)學(xué)模型和分析方法； （5）分析了高應(yīng)力氣門彈簧疲勞壽命試驗(yàn)方法和應(yīng)力水平的設(shè)計(jì)方法；在疲勞壽命試驗(yàn)基礎(chǔ)上，研究了高應(yīng)力氣門彈簧負(fù)荷衰減數(shù)據(jù)統(tǒng)計(jì)和處理方法，給出了不同可靠度水平下負(fù)荷衰減與應(yīng)力循環(huán)次數(shù)的關(guān)系；分析了不同應(yīng)力循環(huán)系數(shù)、不同應(yīng)力水平和不同噴丸條件下高應(yīng)力氣門彈簧負(fù)荷衰減的趨勢；最后在失效模式為指定負(fù)荷衰減率的前提下，運(yùn)用二維概率模型方法給出了基于負(fù)荷衰減的高應(yīng)力氣門彈簧P-S-N曲線的擬合方法和實(shí)例分析。
[Abstract]:Spring is an important part of all kinds of machinery and equipment. In recent years, with the improvement of spring performance requirements, high-stress springs appear. Generally, high stress spring is a spring whose service stress is greater than 800MPa. Its main application fields and products are: high stress spring for automobile, high stress elastic element for high speed locomotive, shock absorber and buffer spring for large engineering machine, Power equipment and piping system balance spring, valve spring, etc. The high stress valve spring is an important basic component in the national medium and long term science and technology development program. Its quality directly affects the performance and safety of the main engine. With the rapid development of economy and technology in China, the requirements of the main engine for high stress valve spring are more and more high, such as lightweight, high reliability and high fatigue life. The high stress valve spring has the characteristics of large design load stress, large variation of stress amplitude, difficult replacement, complex working environment, high fatigue life and high relaxation resistance. Among them, high fatigue life and high anti-relaxation performance requirements are the most important requirements, only to ensure a high fatigue life and anti-relaxation can meet the normal operation of the host during the life cycle. With the further improvement of the design and manufacture level of high stress valve spring, more and more attention has been paid to its fatigue performance and relaxation resistance. Therefore, the reliability analysis of high stress valve spring has been studied in this paper. Based on the above analysis, fatigue reliability analysis of high stress valve spring based on fatigue fracture and fatigue reliability analysis of high stress valve spring based on load attenuation are adopted in this paper. Emphasis has been placed on the following areas of research: 1) the characteristics of fatigue strength and fatigue life of high stress valve spring are systematically studied, and the key factors influencing the fatigue performance of high stress valve spring are given. 2) on the basis of fatigue strength analysis of high stress valve spring, the strengthening principle of shot peening technology to improve fatigue performance of high stress valve spring is studied emphatically, and two strengthening mechanisms of shot peening strengthening are verified by combining relevant theory analysis. The reason of high fatigue reliability requirement of high stress valve spring is analyzed, two kinds of fatigue failure criteria of high stress valve spring are discussed emphatically, and the flow chart of fatigue reliability analysis of high stress valve spring is given. 4) on the premise of traditional fatigue fracture life, the mathematical model and fitting method of P-S-N curve of high stress valve spring based on three-parameter Weibull distribution are studied. On this basis, the reliability mathematical model and analysis method of fatigue residual life of high stress valve spring based on three-parameter Weibull distribution are studied. The fatigue life test method and stress level design method of high stress valve spring are analyzed, and the statistical and processing methods of load attenuation data of high stress valve spring are studied on the basis of fatigue life test. The relationship between the load attenuation and the number of stress cycles at different reliability levels is given, and the trend of load attenuation of high stress valve springs under different stress cycle coefficients, different stress levels and different shot peening conditions is analyzed. Finally, under the premise that the failure mode is the specified load attenuation rate, the fitting method of the P-S-N curve of the high stress valve spring based on the load attenuation and the analysis of an example are given by using the two-dimensional probability model method.
【學(xué)位授予單位】：機(jī)械科學(xué)研究總院
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2012
【分類號(hào)】：TH135

【參考文獻(xiàn)】

相關(guān)期刊論文 前5條

1 王仁智;;論貫穿于冷卷圓簧制造工藝全過程的殘余應(yīng)力[J];中國表面工程;2006年06期

2 吳波,江明湘,江征風(fēng),吳華春;螺旋彈簧疲勞可靠性諸近似計(jì)算模型的比較研究[J];機(jī)械設(shè)計(jì);2004年12期

3 王仁智,姚枚;彈簧表層優(yōu)化噴丸殘余應(yīng)力場的工程計(jì)算方法[J];材料熱處理學(xué)報(bào);2003年04期

4 王仁智，汝繼來，李向斌，姚枚，李金魁，王聲平，邵培革;疲勞裂紋萌生的微細(xì)觀過程與內(nèi)部疲勞極限理論[J];金屬熱處理學(xué)報(bào);1995年04期

5 王仁智;殘余應(yīng)力與彈簧的疲勞性能[J];理化檢驗(yàn).物理分冊(cè);2005年11期

相關(guān)碩士學(xué)位論文 前3條

1 許其峰;超剪切均質(zhì)機(jī)關(guān)鍵結(jié)構(gòu)可靠性分析與研究[D];江南大學(xué);2006年

2 安海;疲勞載荷作用下結(jié)構(gòu)系統(tǒng)的可靠性分析方法的研究[D];哈爾濱工程大學(xué);2006年

3 傅華棟;圓柱螺旋彈簧疲勞試驗(yàn)方法研究[D];機(jī)械科學(xué)研究總院;2007年

本文編號(hào)：1983610