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进气歧管消失模铸造温度场及充型特性的研究 总被引:2,自引:0,他引:2
在对进气管铸件在浇注及冷却过程中各点的温度进行测定的基础上,分析了工艺参数对铸件温度场和充型特性的影响,提出了用消失模铸造工艺批量生产进气管铸件时应注意的问题。 相似文献
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铝合金干砂消失模铸造针孔研究 总被引:3,自引:1,他引:2
本文研究了干砂消失模铸造铝合金针孔形成机制,探讨了铝合金精炼工艺,涂料,浇注温度,真空度等对消失模铸造铝合金的影响,研究结果表明,为减少铝合金铸件的针孔,与普通的空腔铸腔相比,干砂消失模铸造铝合金熔炼时精炼剂用量较多,并需适当提高浇注温度,采用低透气性涂料和提高真空度有助于减少铝合金铸件的针孔。 相似文献
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运用ProCAST软件研究了铝合金铸件的消失模铸造充型过程,考察了不同浇注方式对铸件消失模铸造过程的影响。研究表明,底注式浇注系统的充型相对平稳,是一种比较好的消失模铸造浇注系统方案。浇注系统、浇注速度和界面气隙压力对消失模铸造的充型有很大影响。 相似文献
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根据几种不同类型铝合金变速器壳体的结构特点,结合消失模铸造工艺,得出浇注系统的设计分析对铸件成品率的重要性。通过实验试制和批量生产相结合,研究结果表明:传统的10/12/13档类铝合金壳体,浇注系统设计成底注型;新能源类离合器壳体和中壳体,浇注系统设计成中注型;不带副箱的DS系列类铝合金箱体,部分离合器壳体、后盖类壳体,浇注系统设计成顶注型。以此可以大大提高铸件的成品率,且浇注系统采用实型泡沫。 相似文献
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试验研究了消失模铸造中浇注系统截面比对铝合金铸件品质的影响,确定了适宜的浇注系统截面比.试验结果表明,消失模铸造铝合金铸件宜采用开放式浇注系统,对二单元浇注系统,其截面比是:∑F直∶∑F内=1.00∶(1.30~1.50). 相似文献
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消失模铸造充型过程数值模拟 总被引:3,自引:3,他引:3
运用PROCAST软件对板形铸钢件的消失模充型过程进行了数值模拟。考察了阶梯式浇注系统的充型顺序以及底注式浇注系统的充型形态,另外研究了底注式浇注系统的浇注速度对缺陷形成的影响。模拟结果表明,消失模铸造中,金属液优先从阶梯式浇注系统的上层内浇道充型,充型前沿流动紊乱,铸件容易出现气孔或夹渣;对于底注式浇注系统,充型前沿的流动相对平稳,但过快的浇注速度同样会导致气孔或夹渣缺陷。 相似文献
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回顾了消失模铸造技术的发展历程,现今铸铁和铸钢消失模铸造技术在国内外已相当成熟、应用也较为广泛;而相比之下,铝合金和镁合金的消失模铸造技术发展相对缓慢,尤其在我国铝合金、镁合金消失模铸造技术的推广应用还任重道远.本文着重论述了铝(镁)合金消失模铸造技术的应用现状,指出了当前铝(镁)合金消失模铸造中存在的主要问题,对今后消失模铸造技术的发展趋势进行了展望,介绍了几种适合铝(镁)合金的特种消失模铸造新技术.研究特种消失模铸造新方法,结合金属材质、涂料、热处理工艺、新型泡沫材料和尾气净化技术等开发,是绿色消失模铸造技术的发展方向. 相似文献
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Lost foam casting(LFC)technology has been widely applied to cast iron and cast steel.However,the development of LFC for Al and Mg alloys was relatively slower than that for cast iron and cast steel.The application of LFC to Al and Mg alloys needs more effort,especially in China.In this paper,the development history of LFC is reviewed,and the application situations of LFC to Al and Mg alloys are mainly discussed.Meanwhile,the key problems of LFC for Al and Mg alloys are also pointed out.Finally,the prospects for LFC technology are discussed,and some special new LFC technologies are introduced for casting Al and Mg alloys.In future,the development trends of green LFC technology mainly focus on the special new LFC methods,metal material,coating,heat treatment,new foam materials as well as purification technology of tail gas,etc. 相似文献
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消失模壳型铸造A356铸态和T6态铝合金的组织、性能及拉伸断口(英文) 总被引:2,自引:0,他引:2
对采用消失模壳型铸造制备的A356铝合金在铸态和T6热处理态下的微观组织、拉伸性能以及拉伸断口进行了研究,并与消失模铸造A356铝合金进行了对比分析。结果表明:消失模壳型铸造A356铝合金组织主要有α(Al)初生相、共晶硅相以及Mg2Si相组成。经过T6热处理后,共晶硅形貌更加球化,均匀地分布于晶界处;且共晶硅粒子的平均长度、宽度和长宽比都比铸态条件下的小。与消失模铸造相比,组织中的初生相和共晶硅相都明显细化。经T6处理后,消失模壳型铸造A356合金的力学性能得到明显提高,其中抗拉强度、延伸率和布氏硬度分别达到260.53MPa、6.15%和86.0,其与消失模铸造相比具有明显优势。此外,消失模壳型铸造A356铝合金拉伸断口为具有准解理面和韧窝形貌的混合断口,最终表现为穿晶断裂模式。而消失模铸造A356铝合金拉伸断口为明显的脆性断口。 相似文献
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The microstructure, tensile properties and fractography of A356 alloy were studied under as-cast and T6 conditions obtained with expendable pattern shell casting, and the results were compared with lost foam casting (LFC). The results indicate that a(Al) primary, eutectic silicon and Mg2Si are the main phases in the microstructure of A356 alloy obtained with this casting process. The eutectic silicon particles are spheroidized and uniformly distributed at the grain boundaries after T6 treatment. The average length, average width and aspect ratio of eutectic silicon particles after T6 condition decrease. The sizes of a(Al) primary phase and eutectic silicon of this casting process are smaller than those of LFC. The tensile strength, elongation and hardness of A356 alloy after T6 obviously increase, they reach 260.53 MPa, 6.15% and 86.0, respectively and have a significant improvement compared to LFC. The fracture surfaces of expendable pattern shell casting show a mixed quasi-cleavage and dimple fracture morphology as a transgranular fracture nature. However, the fracture surfaces of LFC display a brittle fracture. 相似文献
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Microstructure and mechanical properties of magnesium alloy prepared by lost foam casting 总被引:3,自引:2,他引:1
The microstructure and mechanical properties of AZ91 alloy prepared by lost foam casting(LFC) and various heat treatments have been investigated. The microstructure of the AZ91 alloy via LFC consists of dominant α-Mg and β-Mg17Al12 as well as a new phase Al32 Mn25 with size of about 5-50μm, which has not been detected in AZ91 alloy prepared by other casting processes. The tests demonstrate that the as-cast mechanical properties are higher than those of sand gravity casting because of chilling and cushioning effect of foam pattern during the mould filling. The solution kinetics and the aging processes at different temperatures were also investigated by hardness and electrical resistivity measurements. The kinetics of aging are faster at the high temperature due to enhanced diffusion of atoms in the matrix, so the hardness peak at 380℃ occurs after 10 h; while at the lower aging temperature(150℃), the peak is not reached in the time(24 h) considered. 相似文献
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延三成 《特种铸造及有色合金》2011,31(11):1036-1037
消失模铸造时,为了满足铸件局部特殊性能要求,在铸件模样局部加入合金元素同时加入稀土元素。铸件成形后,合金元素与稀土元素同时溶入了铸件相对应部位。试验证明,铸件局部合金化可以改善消失模铸件的局部特殊性能。 相似文献
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对我国消失模铸造技术进一步发展的若干建议 总被引:8,自引:1,他引:7
介绍国外消失模技术五年间的最新发展动态 ,对我国消失模铸造技术的发展状况进行重新评估 ,为推动该技术在我国更健康、更快的发展 ,提出了若干重要建议 相似文献
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