本文關(guān)鍵詞：亞穩(wěn)態(tài)奧氏體不銹鋼標(biāo)準(zhǔn)橢圓形封頭溫沖壓溫度研究　出處：《浙江大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

  更多相關(guān)文章： 奧氏體不銹鋼 橢圓形封頭 溫沖壓成形 溫度

【摘要】：亞穩(wěn)態(tài)奧氏體不銹鋼標(biāo)準(zhǔn)橢圓形封頭在工業(yè)中被廣泛使用,為保證產(chǎn)量,該類封頭主要由沖壓工藝生產(chǎn)。然而,冷沖壓成形過程中板料會(huì)發(fā)生形變誘發(fā)馬氏體相變并伴隨著強(qiáng)度的升高和塑性的降低,不利于其安全使用,熱沖壓成形的成本又較高,相比之下,溫沖壓成形即能夠限制沖壓成形后封頭材料的馬氏體量,其成本也明顯低于熱沖壓成形,是較為合適的選擇。目前,關(guān)于封頭溫沖壓成形的研究較少,溫沖壓溫度的制定缺乏理論依據(jù),難以依據(jù)需方對(duì)封頭的馬氏體量的要求來確定合適的沖壓成形溫度,這導(dǎo)致了成本的增高。另外,不了解沖壓溫度對(duì)成形后封頭材料力學(xué)性能的影響,又在無形中增加了安全隱患。此外,由于缺乏有效的方法計(jì)算沖壓成形過程中的溫度下降,也導(dǎo)致了沖壓過程中的溫度下降難以被納入考慮。由此可見,研究沖壓成形溫度對(duì)沖壓成形過程中材料的馬氏體相變以及沖壓成形后材料的力學(xué)性能的影響規(guī)律,建立沖壓成形過程中溫降的計(jì)算方法,將沖壓成形過程中的溫降納入考慮之中,對(duì)保證溫沖壓成形封頭的安全性和經(jīng)濟(jì)性具有重要的意義。綜上所述,本文在浙江省重點(diǎn)科技創(chuàng)新團(tuán)隊(duì)項(xiàng)目(項(xiàng)目編號(hào)2010R50001)、中央高校基本科研業(yè)務(wù)費(fèi)專項(xiàng)資金(項(xiàng)目編號(hào)2014FZA4024)、中國博士后科學(xué)基金(項(xiàng)目編號(hào)2014M551731)等的支持下,主要針對(duì)S30408材料,完成工作如下：(1)基于不同批次304材料在不同溫度下的拉伸試驗(yàn)結(jié)果,分析了材料形變誘發(fā)馬氏體相變隨變形溫度的變化規(guī)律,同時(shí)考慮材料化學(xué)成分的影響,建立了材料形變誘發(fā)馬氏體相變與變形溫度、材料化學(xué)成分之間的關(guān)聯(lián)公式,基于此,初步給出了建議的沖壓溫度下限值為90℃。(2)在第2章的基礎(chǔ)上,通過材料試驗(yàn),研究了材料力學(xué)性能隨其預(yù)變形溫度的變化規(guī)律,并通過對(duì)比各個(gè)溫度下預(yù)變形后材料的力學(xué)性能,進(jìn)一步給出了建議的沖壓溫度下限值,且仍為90℃。(3)進(jìn)行了封頭的溫、冷沖壓成形試驗(yàn)。通過試驗(yàn)對(duì)比了相同規(guī)格的溫、冷沖壓成形封頭的塑性變形率以及成形后各封頭材料的馬氏體量及其沖擊性能,進(jìn)一步驗(yàn)證了以90℃為建議的沖壓溫度下限值的合理性。(4)基于ABAQUS對(duì)溫沖壓成形過程進(jìn)行熱固耦合數(shù)值仿真,對(duì)比試驗(yàn)結(jié)果,建立了封頭溫沖壓成形過程的數(shù)值計(jì)算方法。在此基礎(chǔ)上,采用數(shù)值方法分析了不同溫沖壓條件對(duì)溫降的影響規(guī)律,結(jié)合傳熱學(xué)知識(shí),建立了適用于計(jì)算溫沖壓成形后封頭直邊段溫度的計(jì)算方法。最后,結(jié)合本文所給出的建議的沖壓溫度下限值,給出了考慮溫降的沖壓溫度確定方法。
[Abstract]:The standard elliptical head of metastable austenitic stainless steel is widely used in industry. In order to ensure the output, this kind of head is mainly produced by stamping process. The deformation induced martensite transformation will occur in the cold stamping process with the increase of strength and the decrease of plasticity, which is not conducive to its safe use, and the cost of hot stamping is higher than that of hot stamping. Warm stamping can limit the amount of martensite after stamping, and its cost is obviously lower than that of hot stamping, so it is a more suitable choice. At present, there are few researches on head warm stamping. The establishment of temperature stamping temperature is lack of theoretical basis, it is difficult to determine the appropriate stamping temperature according to the requirement of martensite quantity of the head, which leads to the increase of cost. Do not understand the impact of stamping temperature on the mechanical properties of the head material after forming, but also increase the safety hidden danger in the invisible. In addition, due to the lack of effective methods to calculate the temperature drop in the stamping process. It also leads to the temperature drop in the stamping process is difficult to be taken into account. The effect of stamping temperature on the martensite transformation and mechanical properties of the material during stamping process was studied, and the calculation method of temperature drop in stamping process was established. Taking the temperature drop in the stamping process into account, it is of great significance to ensure the safety and economy of the warm stamping head. This article is in Zhejiang Province key science and technology innovation team project (project number 2010R50001N), the central university basic scientific research business expense special fund (project number 2014FZA4024). Supported by the China postdoctoral Science Foundation (Project No. 2014M551731), it is mainly aimed at material S30408. Based on the tensile test results of different batches of 304 materials at different temperatures, the variation of deformation-induced martensite transformation with deformation temperature is analyzed. At the same time, considering the influence of material chemical composition, the correlation formula between deformation induced martensite transformation and deformation temperature and material chemical composition is established. The suggested lower limit of stamping temperature is 90 鈩，

本文編號(hào)：1370897