本文選題：空心齒輪軸 + 旋鍛��； 參考：《重慶理工大學》2017年碩士論文

【摘要】：汽車齒輪軸是汽車傳動系中傳遞扭矩的一個重要零件。在相同的橫截面積、材料的情況下,空心軸比實心軸承受的外力矩大。若將實心齒輪軸換成空心齒輪軸,可達到減輕汽車自重,從而提高汽車的環(huán)保性和節(jié)能性、降低燃油消耗和減少排放�；谝陨夏康�,本課題以Forge2011軟件對空心齒輪軸進行數(shù)值模擬和正交試驗法優(yōu)化旋轉(zhuǎn)鍛造成形工藝參數(shù),并對旋鍛件進行了物理驗證和等溫正火處理工藝參數(shù)研究。研究情況如下:(1)根據(jù)合作方提供的某型號產(chǎn)品零件結(jié)構(gòu)圖和體積不變原理,對空心齒輪軸的旋鍛成形坯料和成形特點進行分析,通過UG軟件建立了空心齒輪軸坯料、錘頭和芯棒組成的三維模型,并導入Forge2011軟件進行旋鍛成形相關(guān)參數(shù)設(shè)置和多道次文件編寫。(2)主要分析了鍛件轉(zhuǎn)速、錘頭壓下量等各參數(shù)變量對空心齒輪軸溫旋鍛成形的折疊缺陷、有效應(yīng)變、錘頭載荷、溫度梯度的影響。結(jié)果表明:鍛件轉(zhuǎn)速和錘頭壓下量的變化對空心齒輪軸成形的折疊缺陷影響較大;隨著軸向相對送進量的增加,錘頭載荷有相對減弱的趨勢,而隨著錘頭徑向壓下量的增大,錘頭載荷先急劇增大后緩慢增加;軸向相對送進量和徑向速度對坯料溫度梯度影響較顯著,隨軸向相對送進量的增加,第一工序后坯料的最高溫度、最低溫度和第二工序處初始溫度隨之增高,隨著錘頭徑向速度的增加,它們先減小后增大;軸向相對送進量和徑向壓下量對空心齒輪軸成形的螺旋脊椎紋缺陷影響較大,隨著鍛件軸向相對送進量的增大,表面臺階變化越來越急,表面甚至出現(xiàn)了螺旋脊椎紋,最大有效應(yīng)變值先變大后變小,隨著壓下量的增加,最大有效應(yīng)變值逐漸增大,螺旋脊椎紋逐漸明顯;隨著坯料初始溫度和鍛件轉(zhuǎn)速的增大,最大有效應(yīng)變值先逐漸增大后變小,變化急劇程度不一致,有效應(yīng)變分布震幅情況也是先逐漸集中后輻射;隨著錘頭徑向速度的增大,最大有效應(yīng)變值先變小后變大,且變形程度變化不均勻。(3)根據(jù)正交試驗法模擬分析獲得較優(yōu)參數(shù)組為:坯料的初始溫度為830℃,軸向相對送進量為0.05mm,坯料每次轉(zhuǎn)角為23°,錘頭徑向壓下量為2mm,錘頭徑向速度7.5mm/s。物理實驗結(jié)果分析為:從微觀組織分析可知,旋鍛成形使晶粒細化、獲得纖維組織和提高致密性;顯微硬度變化表明了不均勻性變形和晶粒致密性的提高。(4)根據(jù)對試制件不同等溫正火工藝處理研究,獲得較優(yōu)參數(shù)為兩次連續(xù)不同等溫正火工藝,工藝流程為:第一次等溫正火,加熱爐930℃保溫180min,5Hz空氣冷卻至580℃,恒溫爐內(nèi)580℃保溫150min,空氣冷卻至室溫;第二次等溫正火,加熱爐930℃保溫180min;0Hz風冷到580℃;等溫爐580℃保溫150min;空冷至室溫。顯微組織分析得:橫向和縱向是均勻分布的鐵素體-珠光體組織,晶粒度和帶狀組織達到廠家要求。
[Abstract]:Automobile gear shaft is an important part of transmission torque in automobile transmission system. In the case of the same cross-sectional area and material, the external torque of the hollow shaft is greater than that of the solid shaft. If the solid gear shaft is replaced by the hollow gear shaft, the weight of the vehicle can be reduced, the environmental protection and energy saving of the vehicle can be improved, and the fuel consumption and emissions can be reduced. Based on the above purpose, the numerical simulation and orthogonal test of hollow gear shaft were carried out by Forge2011 software, and the technological parameters of rotary forging were optimized, and the physical verification and isothermal normalizing process parameters of rotary forging were carried out. The research results are as follows: 1) according to the structure diagram and volume invariant principle of a certain type of product provided by the partner, the forging blank and forming characteristics of hollow gear shaft are analyzed, and the hollow gear shaft blank is established by UG software. The 3D model composed of hammer head and mandrel is introduced into Forge2011 software to set the relevant parameters of forging forming and to write multi-pass file. (2) the rotational speed of forgings is mainly analyzed. The influence of various parameter variables such as hammerhead reduction on the folding defect, effective strain, hammer load and temperature gradient of the hollow gear shaft in warm rotary forging. The results show that the changes of forging speed and hammerhead reduction have a great influence on the folding defect of hollow gear shafts, and with the increase of axial relative feed amount, the hammer load tends to weaken relatively, but with the increase of the radial reduction of the hammer, The axial relative feed rate and radial velocity have a significant effect on the temperature gradient of the blank. With the increase of the axial relative feed rate, the maximum temperature of the blank after the first working procedure increases. The minimum temperature and initial temperature in the second working procedure increased, and with the increase of the radial velocity of the hammer, they first decreased and then increased, and the axial relative feed and radial reduction had a great influence on the helical spine defects formed by the hollow gear shaft. With the increase of the axial relative feed, the surface step changes more and more rapidly, and even the spiral spine appears on the surface. The maximum effective strain value first increases and then becomes smaller, and with the increase of the reduction, the maximum effective strain value increases gradually. With the increase of the initial temperature of the billet and the rotational speed of the forgings, the maximum effective strain value first increases gradually and then becomes smaller, the change degree is not consistent, and the earthquake amplitude of the effective strain distribution is gradually concentrated first and then radiated. With the increase of radial velocity of hammer head, the maximum effective strain value first decreases and then becomes larger, and the deformation degree varies inhomogeneously. 3) according to the orthogonal test method, the optimum parameters are obtained as follows: the initial temperature of the blank is 830 鈩，

本文編號：2029202