本文選題：鋁合金 + 真空釬焊��； 參考：《合肥工業(yè)大學(xué)》2016年碩士論文

【摘要】：為研制一種適用于6063鋁合金雷達(dá)精密構(gòu)件真空釬焊的低熔點耐腐蝕釬料,通過釬料的熔點測定、電化學(xué)實驗、金相組織觀察、鋪展性實驗和力學(xué)性能試驗,研究Cu、Ge、Ni和Er對釬料組織與性能的影響。研究表明,添加Cu和Ge能形成大量低熔點共晶降低釬料的熔點,3%Ni的添加對釬料熔點的影響不明顯；Ge的添加降低釬料的耐腐蝕性能,3%Ni的添加取代部分Al2Cu中的Cu,提高釬料的耐腐蝕性能。在添加0-0.5%Er的Al-8.5Si-20Cu-5Ge-3Ni釬料中,釬料的熔點隨Er含量的增加逐漸提高。當(dāng)Er的添加量超過0.3%后,釬料的熔點穩(wěn)定在535℃附近,稀土Er降低低熔點脆性相A12Cu的相對數(shù)量,使得釬料的熔點提高。釬料在3.5%NaCl溶液中的耐腐蝕性能隨Er添加量的增大先提高后降低,添加0.2%Er的釬料的耐腐蝕性能最好。稀土Er作為活性元素可以降低液態(tài)釬料的表面張力,釬料的潤濕性隨Er添加量的增加先提高后降低,Er的添加量超過0.2%后,過量的稀土在液態(tài)釬料表面富集形成稀土氧化物降低釬料潤濕性。添加稀土Er可以使釬料的組織趨向細(xì)小均勻化,從而改善釬料的性能。稀土Er可以細(xì)化a-Al枝晶,細(xì)化Al3CuNi和Al2Cu相的混合組織并改善其組織形態(tài),使尖銳的Al2Cu相逐漸轉(zhuǎn)變?yōu)槎檀值墓趋罓?降低Al2Cu相的相對含量。退火態(tài)釬焊接頭的抗剪切強(qiáng)度隨Er含量的增加而升高,添加0.5%Er的釬料釬焊接頭的抗剪切強(qiáng)度達(dá)到最大值47MPa,但是,接頭斷裂處的有效鋪展面積只有50-60%。綜合考慮各組釬料的各項性能,篩選Al-8.5Si-20Cu-5Ge-3Ni-0.2Er釬料為滿足技術(shù)要求指標(biāo)最適宜的釬料。
[Abstract]:In order to develop a low melting point corrosion resistant filler metal suitable for vacuum brazing of 6063 aluminum alloy radar precision components, the melting point, electrochemical, metallographic, spreading and mechanical properties of the solder were measured.The effects of Ni and er on the microstructure and properties of the filler metal were investigated.Research shows thatThe addition of Cu and GE can form a large amount of low melting point eutectic to reduce the melting point of the solder. The effect of adding Ni on the melting point of the solder is not obvious. The addition of GE can reduce the corrosion resistance of the filler metal and the addition of Ni can replace some of the Cus in the solder and improve the corrosion resistance of the filler metal.The melting point of Al-8.5Si-20Cu-5Ge-3Ni filler metal increased with the increase of er content.When er content exceeds 0.3%, the melting point of the filler metal is stable around 535 鈩，

本文編號：1772373