本文選題：低碳鋁鎮(zhèn)靜鋼 + 深沖性能�。� 參考：《華北理工大學(xué)》2015年碩士論文

【摘要】：低碳鋁鎮(zhèn)靜鋼作為一種典型的沖壓用鋼,被廣泛用于汽車制造業(yè)、建筑工業(yè)以及包裝業(yè)等領(lǐng)域,是冶金行業(yè)中產(chǎn)量較高、經(jīng)濟(jì)效益較好的產(chǎn)品之一。針對(duì)唐山某鋼鐵公司生產(chǎn)的低碳鋁鎮(zhèn)靜鋼在沖壓成形過(guò)程中發(fā)生開(kāi)裂現(xiàn)象,研究了開(kāi)裂機(jī)制,找到導(dǎo)致沖壓開(kāi)裂的主要因素;通過(guò)實(shí)驗(yàn)室模擬現(xiàn)場(chǎng)生產(chǎn),調(diào)整工藝參數(shù),控制開(kāi)裂發(fā)生;同時(shí),將最理想的工藝用于現(xiàn)場(chǎng)生產(chǎn),力求解決鋼鐵廠生產(chǎn)的產(chǎn)品沖壓性能不滿足要求的問(wèn)題。采用杯突試驗(yàn)研究鋼板深沖性能不足導(dǎo)致開(kāi)裂的原因,結(jié)果表明,鋼板韌性較好,其斷口呈韌窩狀,但是鐵素體晶粒交界處有粗大碳化物析出,微裂紋就是在碳化物處萌生,所以條片狀的碳化物是導(dǎo)致鋼板開(kāi)裂的主要原因,鋼板裂紋的擴(kuò)展方向與碳化物析出位置一致。在實(shí)驗(yàn)室采用Gleeble試驗(yàn),調(diào)整生產(chǎn)工藝,研究不同工藝條件下滲碳體的析出規(guī)律與析出機(jī)理,結(jié)果表明,終軋溫度和溫降速度對(duì)組織中滲碳體析出規(guī)律影響最大,終軋溫度的升高,鐵素體晶粒有逐步長(zhǎng)大的趨勢(shì),滲碳體析出量也明顯增加。當(dāng)終軋溫度一定時(shí),隨著溫降的降低,鐵素體晶�；颈３植蛔�,滲碳體析出量增加,并出現(xiàn)網(wǎng)狀滲碳體。滲碳體的析出量和析出位置都會(huì)影響鋼板深沖性能,析出量較少且彌散分布的滲碳體對(duì)深沖性能影響較小,以此選擇最佳終軋溫度850℃,溫降速度200℃/min。生產(chǎn)最佳工藝是:出爐溫度1250℃,粗軋溫度范圍1100℃~1050℃,精軋前溫度在1010℃±30℃,終軋溫度850℃±20℃,卷取溫度650℃±10℃。最優(yōu)工藝應(yīng)用于現(xiàn)場(chǎng),結(jié)果與試驗(yàn)室研究相吻合,滲碳體呈彌散分布,對(duì)深沖性能影響最小。
[Abstract]:Low-carbon Al-killed steel, as a typical punching steel, is widely used in automobile manufacturing, construction industry and packaging industry. It is one of the products with higher output and better economic benefit in metallurgical industry. In view of the cracking of low carbon aluminum killed steel produced by Tangshan Iron and Steel Company during stamping forming, the cracking mechanism was studied, the main factors leading to stamping cracking were found, and the process parameters were adjusted by simulating field production in laboratory. At the same time, the most ideal process is used in the field production to solve the problem that the stamping performance of the products produced in the steel plant does not meet the requirements. The causes of cracking caused by insufficient deep drawing properties of steel plate were investigated by cup bursting test. The results show that the steel plate has good toughness and its fracture surface is dimple, but coarse carbides precipitate at the interface of ferrite grains, and microcracks are initiated at carbides. Therefore, the sheet carbide is the main cause of the cracking of the steel plate, and the propagation direction of the crack is consistent with the location of the carbide precipitation. The cementite precipitation law and mechanism under different technological conditions were studied by adjusting the production process by Gleeble test in laboratory. The results showed that the cementite precipitation law was most affected by the final rolling temperature and the temperature drop rate. With the increase of rolling temperature, the ferrite grain tends to grow gradually and the amount of cementite precipitates increases obviously. With the decrease of the temperature drop, the ferrite grain remains unchanged, the amount of cementite precipitates increases, and the net cementite appears when the rolling temperature is fixed. The amount and location of the cementite will affect the deep drawing performance of steel plate. The cementite with less precipitation and dispersion distribution has little effect on the deep drawing property. The optimum rolling temperature is 850 鈩，

本文編號(hào)：1800517