發(fā)布時間：2018-05-06 21:13

  本文選題：玻璃空心微珠 + 無極保溫材料　； 參考：《大連交通大學(xué)》2015年碩士論文

【摘要】：泡沫玻璃保溫板相較于市場上廣為流行的有機保溫板來說,有著不燃、吸水率低等優(yōu)點,但傳統(tǒng)泡沫玻璃保溫板制備工藝有著燒結(jié)溫度高、氣孔孔徑不可控等缺點。本文采用玻璃空心微珠堆燒的方法制備泡沫玻璃保溫材料,研究了玻璃空心微珠在形成保溫板過程中的變化過程及不同燒結(jié)制度對玻璃空心微珠保溫材料性能的影響,試圖尋找燒結(jié)玻璃空心微珠保溫材料的最佳燒結(jié)制度,并利用DTA、SEM、XRD、導(dǎo)熱系數(shù)儀等檢測手段對燒制好的玻璃空心微珠保溫材料進行性能表征。其結(jié)果如下:玻璃空心微珠在達到軟化溫度時開始通過連接頸進行連結(jié),隨著燒結(jié)溫度的提高,連接頸逐漸增大,直至分不出玻璃空心微珠之間的界限,在660℃燒結(jié)時形成一整塊帶有均勻氣孔的玻璃空心微珠保溫材料;之后燒結(jié)溫度的提升造成氣孔的合并、長大其容重逐漸降低。660℃至780℃之間的燒結(jié)溫度燒結(jié),樣品的容重隨著燒結(jié)溫度的提升而降低,超過780℃燒結(jié)時,由于熔融態(tài)玻璃的粘度過低,造成玻璃空心微珠保溫材料內(nèi)的氣體溢出加劇,容重有升高趨勢;在700℃時開始出現(xiàn)析晶現(xiàn)象,隨著燒結(jié)溫度的提升,析晶現(xiàn)象加劇,同時析晶現(xiàn)象會造成物質(zhì)的偏聚,對于孔壁較薄的樣品來說,會顯著提升樣品的開孔率。在700℃燒結(jié)時,保溫時間的延長會使氣相物質(zhì)在熔融態(tài)玻璃中充分的長大,降低樣品的容重,在780℃時則對容重影響不大;但是長時間處于高溫狀態(tài)會造成玻璃成核量加大,導(dǎo)致樣品中析晶的加劇;較低的容重意味著玻璃空心保溫材料內(nèi)氣孔較多,或者氣孔較大,可以顯著降低玻璃空心微珠的導(dǎo)熱系數(shù);而開孔率的增加會使內(nèi)部的氣體流通加劇,造成導(dǎo)熱系數(shù)的提升。提高燒結(jié)時的升溫速率可以加大玻璃空心微珠保溫材料內(nèi)氣相物質(zhì)與熔融態(tài)玻璃的溫差增大,氣相物質(zhì)的熱脹冷縮的幅度也更大,可以降低玻璃空心微珠保溫材料的容重,但降低幅度有限;同時由于并未給予玻璃充分的成核時間,并相對降低了玻璃達到成核溫度的時間,對析晶量的影響較小。經(jīng)實驗確定,在燒結(jié)溫度為780℃,升溫速率為3℃/min,保溫時間為0.5h的樣品具有最佳的綜合性能,其容重為0.131g/cm3,體積吸水率為6.955%,抗壓強度為1.275MPa,同時測得該樣品在25℃(實測23.06℃)的導(dǎo)熱系數(shù)為0.602W/(m?K)。
[Abstract]:Compared with the organic thermal insulation board which is widely used in the market, the foamed glass insulation board has the advantages of noncombustible and low water absorption. However, the traditional preparation process of the foam glass insulation board has the disadvantages of high sintering temperature and uncontrollable pore diameter. In this paper, foam glass insulation materials were prepared by the method of glass hollow bead piling. The change process of glass hollow microbeads in the process of forming insulation board and the influence of different sintering systems on the properties of glass hollow microspheres were studied. This paper attempts to find out the best sintering system of the sintered glass hollow microbeads and to characterize the properties of the sintered glass hollow microbeads by means of DTAA SEM XRD and thermal conductivity meter. The results are as follows: when the glass hollow beads reach the softening temperature, they begin to connect through the connecting neck. With the increase of sintering temperature, the connecting neck increases gradually, until the boundary between the glass hollow beads can not be distinguished. When sintered at 660 鈩，

本文編號：1853888