本文選題：固-液復(fù)合 + 鋁/鋁復(fù)合��； 參考：《吉林大學(xué)》2017年碩士論文

【摘要】：伴隨著21世紀的步伐,世界的科學(xué)技術(shù)和工業(yè)生產(chǎn)都得到迅猛的突破和發(fā)展,由過共晶鋁硅合金制造的缸套,可實現(xiàn)“全鋁型發(fā)動機”的制備,有助于提高發(fā)動機的效率、延長使用壽命等,對汽車行業(yè)的發(fā)展、環(huán)境保護及節(jié)約能源等各個方面起著重要的作用。目前,各國對過共晶鋁硅合金缸套材料的研究相對成熟,也不斷加強對缸套/缸體總成一體技術(shù)的研發(fā),但每種方法都相對復(fù)雜,并存在一定的問題。由于鑲鑄技術(shù)方法簡單,對固態(tài)鑲鑄件沒有大小、形狀、尺寸及材質(zhì)等要求,得到廣泛的使用,本文為了更好地貼近實際生產(chǎn),以最小的成本和資源達到最優(yōu)的冶金結(jié)合,采用砂型鑄造、重力澆注的方法,通過鋁/鋁固-液雙金屬復(fù)合成型工藝的實驗,研究表面處理對鋁/鋁固-液雙金屬復(fù)合成型工藝的影響,即粗糙表面處理、光滑打磨處理、電鍍鋅處理、電鍍鎳處理、電鍍銅處理對復(fù)合界面和組織的影響;以電鍍銅為例,探討了陰極電流密度對電鍍層的影響、電鍍時間與電鍍層厚度的關(guān)系,并研究澆注溫度、預(yù)熱溫度、電鍍時間對雙金屬復(fù)合成形界面的影響。通過本文的研究,主要得出以下結(jié)論:1)表面粗糙、光滑處理無法使得鋁/鋁固-液雙金屬達到冶金結(jié)合,其根本原因是界面的氧化層阻礙雙金屬的潤濕,而且在澆注過程中鋁合金預(yù)制塊表面會二次氧化,導(dǎo)致界面結(jié)合差。2)電鍍鋅、鎳、銅處理均有助于固-液雙金屬的冶金結(jié)合,鋅、鎳、銅元素向兩側(cè)界面擴散,鎳、銅在擴散過程中有聚集現(xiàn)象發(fā)生。在澆注溫度750℃、電鍍15min、預(yù)熱溫度為100℃條件下,相比于其他兩種處理方法,電鍍銅處理后鑄件的剪切強度最高為23.45MPa,銅元素的擴散最遠距離約為400μm。3)電流密度5A/dm2為最佳電流密度,電鍍銅層表面平整良好、無毛刺和氣泡等,電鍍層質(zhì)量與基體之間的結(jié)合符合電鍍沉積標準。當電鍍時間分別是5min、10min、15min時,獲得實際的銅鍍層厚度分別為是6.46μm、8.18μm、10.24μm。4)在澆注溫度為780℃,電鍍時間為10min,預(yù)熱溫度為100℃的條件下,可得最大的雙金屬復(fù)合界面剪切強度為28.23MPa,各參數(shù)對界面結(jié)合影響的主要次序是澆注溫度、電鍍時間、預(yù)熱溫度。過高的澆注溫度會使預(yù)制塊表面熔化加劇,甚至導(dǎo)致變形,經(jīng)綜合考慮,認為澆注溫度為750℃,電鍍時間為15min,預(yù)熱溫度為100℃,為最佳工藝參數(shù)。
[Abstract]:With the pace of the 21st century, the world's science and technology and industrial production have been a rapid breakthrough and development. The cylinder liner made of hypereutectic Al-Si alloy can realize the preparation of "all-aluminum engine" and help to improve the efficiency of the engine. Prolonging service life plays an important role in the development of automobile industry, environmental protection and energy conservation. At present, the research on hypereutectic Al-Si alloy cylinder liner materials is relatively mature, and the research and development of cylinder liner / cylinder block assembly technology has been strengthened, but each method is relatively complex, and there are some problems. Because of the simple technology and the lack of size, shape, size and material for solid castings, this paper aims to be more close to the actual production and to achieve the best metallurgical combination with the minimum cost and resources, in order to be more close to the actual production, and to achieve the best metallurgical combination with the minimum cost and resources. By means of sand mold casting and gravity casting, the effect of surface treatment on aluminum / aluminum solid liquid bimetallic composite molding process was studied through the experiments of aluminum / aluminum solid liquid bimetallic composite molding process, namely rough surface treatment, smooth grinding treatment, The effect of zinc plating, nickel plating and copper plating on the composite interface and structure was studied, and the effect of cathode current density on the electroplating layer, the relationship between plating time and the thickness of the plating layer, and the pouring temperature were studied, taking the electroplating copper as an example, the effect of cathodic current density on the electroplating layer was discussed. Effects of preheating temperature and electroplating time on bimetallic composite forming interface. Through the research in this paper, we can draw the following conclusion: 1) rough surface, smooth treatment can not make aluminum / aluminum solid liquid bimetallic metallurgical bonding, the basic reason is that the oxidation layer of interface hinders the wetting of bimetallic. Moreover, during the casting process, the surface of the prefabricated aluminum alloy will be reoxidized, resulting in the interface bonding difference. 2) the treatment of zinc, nickel and copper all contribute to the metallurgical bonding of solid liquid bimetallic, and the elements of zinc, nickel and copper diffuse to both sides of the interface. Copper aggregates in the diffusion process. Under the conditions of pouring temperature 750 鈩，

本文編號：1883227