本文關(guān)鍵詞：激光相變硬化對(duì)亞共析鋼接觸疲勞的影響　出處：《南京航空航天大學(xué)》2016年碩士論文　論文類型：學(xué)位論文

  更多相關(guān)文章： 亞共析鋼 激光相變硬化 接觸疲勞 有限元 數(shù)值模擬

【摘要】：高速列車行駛過(guò)程中,車輪與鋼軌的型面匹配極其重要,型面不匹配會(huì)產(chǎn)生振動(dòng)、噪聲,影響列車運(yùn)行的平穩(wěn)性、舒適性,甚至影響安全性。在型面匹配的條件下,輪緣磨損和踏面疲勞是車輪失效的主要原因。由于輪緣與軌側(cè)磨損主要是滑動(dòng)磨損,通常要比踏面磨損嚴(yán)重,為了達(dá)到型面匹配,需進(jìn)行定期的鏇修,少量的輪緣鏇修往往伴隨大量的踏面鏇修,僅僅輪緣的磨損卻導(dǎo)致基本完好的踏面也要被車削掉,造成了極大的浪費(fèi)。激光相變硬化工藝加熱及冷卻速度極快,生成的馬氏體組織晶粒細(xì)小、位錯(cuò)密度高,使相變硬化層具有比常規(guī)淬火更高的硬度,零件內(nèi)部的材料也能保持原有的韌性,大量研究表明,激光相變硬化可以顯著提高鋼的耐磨性,但是其對(duì)輪軌間的滾動(dòng)接觸疲勞影響還有待研究。本文討論了不同激光相變硬化工藝參數(shù)對(duì)硬化層組織、硬度、殘余應(yīng)力大小及殘余奧氏體含量的影響,以便設(shè)計(jì)合適的激光相變硬化工藝。對(duì)經(jīng)激光相變硬化處理的車輪鋼試樣進(jìn)行摩擦磨損實(shí)驗(yàn)以及滾動(dòng)接觸疲勞實(shí)驗(yàn),驗(yàn)證了激光相變硬化工藝對(duì)亞共析鋼耐磨性及抗疲勞性能的影響。通過(guò)X射線應(yīng)力大小測(cè)定、殘奧含量測(cè)定、顯微硬度測(cè)量、SEM等分析技術(shù),探究了亞共析鋼的滾動(dòng)接觸疲勞機(jī)理,并得出了激光相變硬化技術(shù)改善亞共析鋼抗疲勞性能的原因。采用有限元計(jì)算方法,模擬激光相變硬化過(guò)程的溫度場(chǎng),并預(yù)測(cè)大功率激光器可能獲得的硬化層深度,為激光相變硬化處理高速列車車輪提供理論依據(jù),通過(guò)溫度場(chǎng)與相變場(chǎng)的結(jié)合,模擬了激光相變硬化層的硬度值。
[Abstract]:During high-speed train running, the matching between wheel and rail surface is very important. Surface mismatch will produce vibration and noise, which will affect the ride comfort, comfort and even safety of trains. The wheel flange wear and the tread fatigue are the main causes of the wheel failure under the condition of the surface matching. Because of the rim and the rail side wear is the main wear, usually tread wear, in order to reach the surface, need regular lathing, small rim lathing are often accompanied by a lot of tread wear repair, only rim has led to the basic well tread will be turning off, cause a great deal of waste. Laser hardening process of heating and cooling speed, the martensite microstructure with fine grains, high dislocation density is generated, the hardened layer is higher than the conventional quenching hardness, parts of the internal material can maintain the original toughness, a large number of studies show that laser transformation hardening can improve the wear resistance of steel, but the the rolling contact fatigue effect between wheel and rail remains to be studied. In this paper, the effects of different laser transformation hardening parameters on hardened layer structure, hardness, residual stress and retained austenite content are discussed, so as to design suitable laser transformation hardening process. The effect of laser transformation hardening process on wear resistance and fatigue resistance of hypoeutectoid steel was verified by friction and wear test and rolling contact fatigue test. The mechanism of rolling contact fatigue for hypoeutectoid steel was investigated by means of X ray stress measurement, residual content determination, microhardness measurement and SEM analysis. The reasons for improving fatigue resistance of hypoeutectoid steel were obtained by laser transformation hardening technology. By using the finite element method, numerical simulation of temperature field during laser transformation hardening, and predict the depth of hardened layer of high power laser may be obtained, for laser hardening and provide a theoretical basis for the high speed train wheel, through the combination of field and phase change temperature field, the simulation of laser hardened layer hardness.
【學(xué)位授予單位】：南京航空航天大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2016
【分類號(hào)】：TG142.1;TG665

【參考文獻(xiàn)】

相關(guān)期刊論文 前7條

1 畢于順;宋雷明;;調(diào)質(zhì)型鋼板的體積膨脹分析[J];安徽冶金;2014年01期

2 汪舟;姜傳海;Volker Schulze;陳艷華;嵇寧;;不同光束移動(dòng)速度下的激光淬火有限元分析[J];材料科學(xué)與工藝;2011年04期

3 潘健生,張偉民,田東,顧劍鋒,胡明娟;熱處理數(shù)學(xué)模型與計(jì)算機(jī)模擬[J];中國(guó)工程科學(xué);2003年05期

4 路綱,席守謀;4Cr13鋼激光相變強(qiáng)化機(jī)理研究[J];金屬熱處理學(xué)報(bào);2002年04期

5 金學(xué)松,沈志云;輪軌滾動(dòng)接觸疲勞問(wèn)題研究的最新進(jìn)展[J];鐵道學(xué)報(bào);2001年02期

6 朱桂蘭,馬騰;稀土對(duì)鋼軌鋼接觸疲勞的影響[J];鋼鐵研究學(xué)報(bào);1999年02期

7 蘇寶蓉,余弘波;激光熱處理發(fā)展現(xiàn)狀[J];上海金屬;1994年03期

，

本文編號(hào)：1343837