铝硅铜合金液态模锻工艺

在ZL102合金中加入4%的铜为原料,采用正交试验方法进行工艺实验研究,确定了最佳工艺参数。实验结果表明,采用液态模锻工艺,制件力学性能明显提高,热处理后组织得到细化,硅颗粒分布均匀;Al2Cu强化相析出,使得抗拉强度比热处理前的抗拉强度提高11.8%,比金属型提高44.5%。     

Microstructure evolution of cast Al-Si-Cu alloys in solution treatment

To develop a software to predict the evolution of microstructure and the development of mechanical properties during the heat treatment of cast aluminum alloys, we modeled the redistribution of solute during the solution treatment of multicomponent alloys. The predictions of solidification simulation software or the results of experiment provided the initial microstructure and solute distribution for simulation of heat treatment. Binary through quinary aluminum alloys with silicon, copper, magnesium, and iron were modeled. The basic model assumed local equilibrium （no undercooling due to nucleation or growth） and computed diffusion in the solid constituents during solidification. The evolution of microstructure during solution treatment was followed by qualitative and quantitative metallography. The results of simulation for the ternary alloy Al-7%Si-3.5%Cu were compared to experimental observation.     

Study on the Microstructure and Wettability of an Al-Cu-Si Braze Containing Small Amounts of Rare Earth Erbium

The effect of adding small amounts of rare earth Er on the microstructure of an Al-Cu-Si braze alloy has been investigated. Several Al-20Cu-7Si braze alloys containing various contents of Er were prepared, and their melting temperature, microstructure, hardness, and wettability in contact with 3003 aluminum alloy substrates were determined. The results indicate that the constituents of the microstructure of Al-20Cu-7Si-Er braze alloys are similar to those in the Al-20Cu-7Si alloy, and comprise of solid solutions of aluminum, silicon, and the intermetallic compound CuAl₂. When the Er content increases, the size of the Al phase decreases, and the needle-like Si phase is thickened, and transformed to a blocky shape. Moreover, small amounts of Er can improve the wettability and hardness of the Al-20Cu-7Si braze alloy; however, the melting temperature of the Al-20Cu-7Si alloy does not change.     

硅相对铜在Al-Si-Cu合金中扩散速度影响的研究

测定了铜在单相α合金（Al-1．5wt％Cu-0．4wt％Si）和α＋Si两相合金（Al-1．5wt％Cu．12．5wt％Si）中的扩散系数。单相α合金扩散偶（Al-3．0wt％Cu-0．4wt％Si／Al-0．4wt％Si）和α＋si两相合金扩散偶（Al-3．0wt％Cu．12．5wt％Si／Al-12．5wt％Si）在450—540℃条件下保温72—144h后，用电子探针测定铜原子的浓度分布，并由此计算铜原子在这两种基体中的扩散系数。测定结果表明，硅相的存在能够显著提高铜在该合金中的扩散速度，提高的幅度取决于硅相的体积分数和形貌。     

耐磨铝硅铜合金的双面搅拌摩擦焊

对10 mm厚的铝硅铜合金进行了双面搅拌摩擦焊接,研究了焊接接头的显微组织及力学性能.研究表明,铸态金属晶粒和硅粒子在双面搅拌摩擦焊接过程中得到细化,硅颗粒分布均匀化.反面焊道比正面焊道的晶粒细化和硅粒子均匀化作用更明显.异向焊接的接头强度较低,所有接头均断在焊缝的前进侧.同向焊接的接头强度较高,接头断裂位置取决于焊接参数.选用搅拌头旋转频率为950 r/min、焊接速度为10mm/min的参数焊接时,同向接头表面成形好、内部无缺陷,其强度可达母材的87.4%.     

铝硅铜合金对压铸模设计的要求

通过对铝硅铜合金工艺特性的研究，提出选定合理的压铸模成形零件配合间隙的必要性的并模具温控装置，模具中间退火等工艺措施，达到既提高压铸件的质量，又延长压铸模使用寿命的目的。     

Study on Al-Cu-Si braze containing small amount of rare earth erbium

In the present work, the effect of a small amount of rare earth Er addition on the microstructure of Al-Cu-Si brazing alloy has been investigated. In the study, the Al-20Cu-7Si brazing alloys with various Er contents were prepared. 3003 aluminum alloy was chosen as a substrate. The microstructure of the brazed alloys was carefully observed. In addition, melting temperature, wettability and hardness of the brazing alloys were measured. The results indicate that the constituent of the microstructure of Al-20Cu-7Si-Er brazed alloy is similar to the Al-20Cu-7Si, which is mainly comprised of solid solutions of aluminum, silicon and the intermetallic compounds CuAl₂. When the Er content increases, the size of Al phases is decreased, and the filament-like or needle-like Si phase is thickened. The Si phases dominating in the shape of a filament or needle are transformed to those in the shape of a block when Er content is increased. Moreover, adding a small amount of Er can improve the wettability and hardness of the Al-20Cu-7Si brazing alloy. However, the melting temperature of the Al-20Cu-7Si alloy is almost unchanged when a small amount of Er is added.     

退火对快速凝固Al-Si-Cu合金脆性的影响

用平板压弯法及各种分析方法研究单辊急冷法制备的Al-Si-Cu薄带的脆性及退火处理对其脆性的影响。结果表明,在晶界呈网状分布的θ'和口θ'相是产生脆性的根本原因。采用适当的退火热处理工艺可以使θ'和θ'相脱溶析出,因此可显著提高快冷Al-Si-Cu薄带的韧性。     

Synthesis and characterization of carbon nanotubes reinforced Al-Si-Cu brazing powder

In this paper, an approach to synthesizing carbon nanotubes （ CNTs ） reinforced A1-Si-Cu brazing powder was studied, which was accomplished by in-situ growth of the CNTs on the Al-Si-Cu powder at a relatively low temperature by plasma enhanced chemical vapor deposition （ PECVD ）. The synthesis parameters were optimized. The component of brazing powder was analyzed by X-ray diffraction （ XRD ）. The microstracture and dispersity of as-grown CNTs were investigated by scanning electron microscopy （SEM）. The graphitization and defects were characterized by Raman spectroscopy. The asgrown CNTs on Al-Si-Cu powder disperse uniformly and have moderate length and density, meanwhile its sp2 structure dominates minor quantity of amorphous carbons and defected carbon structures.     

新型半固态成形用Al-Si-Cu合金的成分设计

借助Thermo-Calc软件分析了Al-Si-Cu合金的热力学特点,结合半固态成形所需条件,提出了该系合金适合半固态成形的成分区间,并对AlSi5Cu3Mg合金半固态坯料的加热过程进行验证。结果表明,获得的半固态坯料完全满足半固态成形的组织需要。