本文關(guān)鍵詞：鎂合金低壓消失模鑄造典型缺陷試驗研究，由筆耕文化傳播整理發(fā)布。

華中科技大學(xué)碩士學(xué)位論文

鎂合金低壓消失模鑄造典型缺陷試驗研究

姓名：張大付申請學(xué)位級別：碩士專業(yè)：材料加工工程指導(dǎo)教師：樊自田

20050430

摘　　要　

鎂合金因密度小

成型困難的缺點(diǎn)

低壓

消失模鑄造新技術(shù)

建立了低壓消失模鑄造過程中金

屬液充型的物理和數(shù)學(xué)模型

用電極觸點(diǎn)法記錄了鎂合金低壓消失模

鑄造的充型過程

粘砂等典型缺陷，　分析了這些缺陷的形貌特征

提出了減少和消除缺陷的工藝措施

低壓消失模鑄造新工藝的充型能力大大高于重力消失模鑄造

低壓消失模鑄造能獲得輪廓清晰的鎂合金薄壁復(fù)雜鑄件薄壁的鎂

在可控的壓力及氣氛下充型和凝固涂層性能

目的．　　

關(guān)鍵字

澆注系統(tǒng)等多方面因素

氣孔等缺陷之

鋁

電子工業(yè)中的應(yīng)用迅速增長

Abstract

In the last 10 years, there is a rapid growth of application of magnesium (Mg) alloys in the auto and electronic industries because of its low density and high strength-to-weight ratio, and the lost foam casting (LFC) process is a precision forming technology capable of casting complicated parts with low manufacturing costs. In order to overcome the shortcomings of melt Mg alloy quick oxidation and mould filling difficulty, the Huazhong University of Science and Technology developed a new Low Pressure- Lost Foam Casting (LP-LFC) process for producing Mg alloy castings with thin-wall and complex geometries by combining benefits of LFC with the superiority of low pressure casting (LPC).

This paper analyzes the principle of the LP-LFC process

the casting defects

including short runs, cold laps, trapped gas

birth causes and influence factors of above defects are

discussed in the article

and the new process can largely reduce

or overcome the defects of short runs and cold laps encountered in LFC. The complex thin-walled Mg alloy (or Al alloy) castings can be produced perfectly by LP-LFC, so the new process is very suitable for casting Mg alloy (or Al alloy) parts with high precision and complex thin-walled.

In LP-LFC process, the mould filling and metal freezing are carried out under the controllable pressure and gas environment. The filling course and the defects of short runs and trapped gas are mainly depended on the pressure and flux of filling gas, foam pattern

property, pouring temperature, coating performance, gating system

１　　緒論　

1.1

課題來源

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ì?±eê???3μ

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輕的鎂合金材料和消失模鑄造成型技術(shù)的結(jié)合正好滿足了這兩個方面的設(shè)計原則

輕的鎂合金

優(yōu)化結(jié)構(gòu)

比強(qiáng)度

抗輻射能力和減震性強(qiáng)

精確成形

符合21

世紀(jì)鑄造的發(fā)展方向

而且鎂資源豐富

消失模技術(shù)的最大特點(diǎn)是鑄件設(shè)計非常靈活

減少加工

從產(chǎn)品的結(jié)構(gòu)輕量化復(fù)雜

特別是汽車

術(shù)的結(jié)合順應(yīng)了時代發(fā)展要求

消失模鑄造工藝的特點(diǎn)非常適合鎂合金液態(tài)成型華中科技大學(xué)

提出了把鎂合金

成一種非常適用于優(yōu)質(zhì)壓鎂合金消失模精密鑄造技術(shù)

鎂合金消失模鑄件缺陷真空低壓消失模鑄造

形

即可控氣壓下真空低

因此鎂合金材料和消失模鑄造技

鎂及其合金有如下優(yōu)勢

[8]

1

2

強(qiáng)的減震性

6

高純度鎂具有更高的抗腐蝕性

塑料

１

耐老化３

  本文關(guān)鍵詞：鎂合金低壓消失模鑄造典型缺陷試驗研究，由筆耕文化傳播整理發(fā)布。