本文選題：銅-鎳合金　切入點(diǎn)：熔煉工藝　出處：《南昌航空大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：隨著冶煉強(qiáng)度的不斷加大,高爐爐襯的保護(hù)技術(shù)變得越來越重要,目前通用的解決方法是在砌磚之間埋設(shè)具有高熱導(dǎo)率的純銅水套,實(shí)行強(qiáng)制冷卻,延長(zhǎng)高爐使用壽命。然而純銅水套存在3個(gè)不可避免的缺點(diǎn),一是水套鑄造過程中易熔穿,二是在實(shí)際使用過程中由于高爐內(nèi)溫度較高,只要水量、水壓或水溫稍有波動(dòng),水套即可能迅速熔穿,三是純銅熱導(dǎo)率過高易產(chǎn)生“氣錘”的負(fù)面影響。究其原因是由于純銅的熔點(diǎn)較低,開發(fā)高熔點(diǎn)高熱導(dǎo)銅合金對(duì)研制高性能冷卻水套等熱交換器件意義重大。本文依據(jù)銅合金相圖,在Cu-Ni合金基礎(chǔ)之上,添加Mo、Nb、Y等元素,分別制備了Cu-Ni-Mo、Cu-Ni-Nb-Y和Cu-Ni-Nb-Mo合金,系統(tǒng)研究了合金成分及熔煉工藝對(duì)合金組織、熔點(diǎn)、熱導(dǎo)率和硬度的影響規(guī)律,獲得如下結(jié)論:(1)同一成分下,電弧熔煉水冷銅坩堝制備工藝比感應(yīng)熔煉石英玻璃坩堝制備工藝所獲得的Cu-Ni-Mo合金組織粗大、熱導(dǎo)率穩(wěn)定,電弧熔煉制備的Cu-Ni-Mo合金的熔點(diǎn)和硬度更高。(2)Cu-Ni-Mo合金,Mo元素的增加對(duì)兩種熔煉方式下制備的合金熔點(diǎn)影響不大,但當(dāng)合金組織中出現(xiàn)Mo相時(shí),合金熔點(diǎn)明顯提高。(3)在Cu-Ni-Nb合金中添加微量稀土元素Y,能夠細(xì)化合金組織,能使合金組織中的第二相愈發(fā)粗長(zhǎng),Y元素能改善合金熱導(dǎo)率,對(duì)于合金熔點(diǎn)來說,Y元素卻對(duì)Cu-Ni-Nb合金有負(fù)面的影響,Y元素對(duì)于合金硬度的影響很小,單從細(xì)化組織方面影響合金硬度。(4)Cu-Ni-Nb-Mo合金,當(dāng)Ni元素含量一定時(shí),隨著Nb、Mo的增加,合金組織中第二相增加,改善了合金熱導(dǎo)率,但會(huì)使合金熔點(diǎn)降低。(5)本文條件下,各元素對(duì)Cu-Ni-Nb-Mo合金熱導(dǎo)率和熔點(diǎn)影響的主次因素順序都為Ni-Nb-Mo,Ni元素對(duì)銅合金導(dǎo)熱率和熔點(diǎn)的影響是顯著的,合金中元素Ni含量越高,合金熱導(dǎo)率下降越大,合金熔點(diǎn)越高,其次要因素是Nb,末要因素是Mo;(6)本文條件下,采用正交實(shí)驗(yàn)綜合平衡法得出高導(dǎo)熱率高熔點(diǎn)銅合金的最優(yōu)成分為Cu-15Ni-3Nb-2Mo,其熱導(dǎo)率為54.70 W/m·k,熔點(diǎn)為1131.59℃。
[Abstract]:With the increasing of smelting strength, the protection technology of blast furnace lining becomes more and more important. At present, the common solution is to install pure copper water jacket with high thermal conductivity between masonry, and to carry out forced cooling. The service life of blast furnace is prolonged. However, there are three unavoidable disadvantages of pure copper water jacket. One is that the water jacket is fusible in casting process, the other is that the temperature in blast furnace is higher in actual use, so long as the water quantity, water pressure or water temperature fluctuate slightly, The water jacket is likely to melt through quickly, and the third is that the high thermal conductivity of pure copper is liable to produce the negative effect of "air hammer". The reason is that the melting point of pure copper is low. The development of high melting point and high thermal conductivity copper alloy is of great significance to the development of high performance cooling water jacket and other heat exchangers. Based on the phase diagram of copper alloy and on the basis of Cu-Ni alloy, the Cu-Ni-Mo-Mo Cu-Ni-Nb-Y and Cu-Ni-Nb-Mo alloys were prepared, respectively. The effects of alloy composition and melting process on the microstructure, melting point, thermal conductivity and hardness of the alloy were systematically studied. The Cu-Ni-Mo alloy prepared by arc melting water-cooled copper crucible is thicker than that obtained by induction melting quartz glass crucible, and its thermal conductivity is stable. The melting point and hardness of the Cu-Ni-Mo alloy prepared by arc melting have a little effect on the melting point of the alloy prepared under the two melting modes, but when Mo phase appears in the microstructure of the alloy, the increase of Mo element in Cu-Ni-Mo alloy has little effect on the melting point of the alloy. The melting point of the alloy is obviously increased. 3) adding trace rare earth element Y to the Cu-Ni-Nb alloy can refine the microstructure of the alloy and improve the thermal conductivity of the alloy by increasing the second phase of the second phase and increasing the length of Y element. For the melting point of the alloy, Y element has a negative effect on the hardness of the Cu-Ni-Nb alloy. The effect of Y element on the hardness of the alloy is very small. The hardness of the alloy, Cu-Ni-Nb-Mo alloy, is affected only by refining the microstructure. When the content of Ni element is constant, with the increase of the content of Ni element, the effect of Y element on the hardness of the alloy is very small. The increase of the second phase in the microstructure of the alloy improves the thermal conductivity of the alloy, but reduces the melting point of the alloy. The order of the primary and secondary factors influencing the thermal conductivity and melting point of Cu-Ni-Nb-Mo alloy is that the effect of Ni-Nb-Mo-Ni element on the thermal conductivity and melting point of copper alloy is significant. The higher the Ni content in the alloy, the greater the thermal conductivity of the alloy and the higher the melting point of the alloy. In this paper, the optimum composition of Cu alloy with high thermal conductivity and high melting point is Cu-15Ni-3Nb-2Mo.The thermal conductivity of Cu-15Ni-3Nb-2Moand the melting point of Cu-15Ni-3Nb-2Mois 54.70W / m 路k, and the melting point is 1131.59 鈩，

本文編號(hào)：1564044