發(fā)布時間：2018-05-19 18:30

  本文選題：玻璃鋼化 + 溫度場　； 參考：《武漢科技大學》2015年碩士論文

【摘要】：鋼化可以消除或減少玻璃表面的微裂紋，改善其機械性能，提高其熱穩(wěn)定性。冷卻是鋼化的最后一道工藝，由于冷卻過程中板面冷卻均勻性很難保證、各點冷卻時間長短不一，易產(chǎn)生玻璃自爆或表面應(yīng)力斑，降低玻璃鋼化質(zhì)量。為此，需預(yù)控冷卻過程，穩(wěn)定鋼化質(zhì)量，主要包括： 分析冷卻過程中工藝控制需求，確定冷卻速度和冷卻時間為預(yù)控對象；根據(jù)傅里葉定律和玻璃應(yīng)力松弛、結(jié)構(gòu)弛豫特點，建立冷卻速度與溫度場之間關(guān)系模型、溫度與玻璃粘彈性本構(gòu)模型；推導(dǎo)冷卻速度與殘余應(yīng)力之間變化關(guān)系，建立預(yù)控數(shù)學模型，通過冷卻速度的調(diào)整，實現(xiàn)殘余應(yīng)力的預(yù)控�；谟邢拊治龇椒�，建立玻璃鋼化冷卻過程中溫度、應(yīng)力變化過程的仿真模型。 運行預(yù)控模型和進行多組仿真實驗，獲得相關(guān)結(jié)果：設(shè)定玻璃厚5mm及對流換熱系數(shù)為190W/(m2K)，在前40s內(nèi)應(yīng)以0.375℃/s2勻減速加壓急冷，，在40s到80s間以0.125℃/s2均減速冷卻，從而可約在7s時于玻璃板中心線上獲得高達151℃的溫差，保證鋼化程度；在10s內(nèi)將玻璃溫度降到轉(zhuǎn)變溫度區(qū)以下，基本定型玻璃結(jié)構(gòu)；獲得近似拋物線的殘余應(yīng)力分布，可提供玻璃受力時所需的預(yù)應(yīng)力。證明所建立的預(yù)控數(shù)學模型具有一定的準確性和可靠性，可為實際生產(chǎn)提供一定的參考或指導(dǎo)。
[Abstract]:Toughening can eliminate or reduce the microcracks on glass surface, improve its mechanical properties and improve its thermal stability. Cooling is the last process of tempering. Because the uniformity of plate cooling is difficult to guarantee during the cooling process, the cooling time varies from point to point, so it is easy to produce glass self-explosion or surface stress spot, and reduce the quality of glass toughening. Therefore, it is necessary to pre-control the cooling process and stabilize the tempering quality, including: According to Fourier law, glass stress relaxation and structure relaxation, the relationship between cooling rate and temperature field is established. The relationship between cooling rate and residual stress is deduced and the mathematical model of pre-control is established. The residual stress is controlled by adjusting the cooling rate. Based on the finite element analysis method, the simulation model of temperature and stress change in the process of glass tempering and cooling is established. The results are as follows: set the glass thickness 5mm and convection heat transfer coefficient to be 190W / m ~ (2) K ~ (-1), 0.375 鈩

本文編號：1911177