铝合金化学镀镍磷合金镀层的组织和相结构

介绍了铝合金化学镀镍磷合金镀层的初期析出行为、组织和相结构。镀态下，镀层截面组织为黑白分明的层状组织，平面组织呈同心环状。低磷镀层的相结构是磷在镍中的过饱和固溶体，而高磷镀层为非晶态镍磷合金。随着加热温度的升高，低磷镀层的相结构是磷在镍中的过饱和固溶体，而高磷镀层为非晶态镍磷合金。随着加热温度的升高，低磷镀层首先析出ＮｉｘＰｙ，然后析出Ｎｉ３Ｐ相。高磷非晶态镀层首先晶化转变成ＮｉｘＰｙ相和Ｎｉ３Ｐ     

细晶铝锭熔炼的A356铝合金组织与性能的研究

研究了不同细化和变质方法对细晶铝锭熔炼的A356铝合金组织与性能的影响。结果表明,钛(由细晶铝锭加入)、硼及稀土联合细化,晶粒细化效果最好;0.04%的锶、0.01%的钛、0.03%的硼及0.3%的稀土联合细化及变质的A356铝合金晶粒细小,硅颗粒细碎,气孔较少,具有较高的力学性能。     

Ti、Sc、Zr对铝合金微观组织的影响

制备了含Ti、Sc、Zr的铝合金,测量了平均晶粒直径和硬度,并利用金相显微镜、XRD、SEM和EDS等方法研究其细化及强化机理。结果表明：Ti元素能显著细化合金的晶粒,但不能提高合金的硬度;0.2%Sc对合金晶粒细化不太显著,但对硬度提高非常显著;0.13%Zr添加时,其细化效果略好于0.20%Sc,而对硬度的影响略低于0.20%Sc;当三者同时添加时,得到较好的细化及强化效果。     

细化及变质方法对A356铝合金微观组织的影响

在对比研究细晶铝锭和铝钛中间合金2种不同加钛细化方法的基础上,研究锶、稀土、锶 稀土不同变质方法处理后A356铝合金的铸态微观组织变化。结果表明:细晶铝锭细化效果较铝钛中间合金好,经细晶铝锭 锶 稀土联合处理的A356铝合金,晶粒细小,变质充分,针孔较少,组织均匀,是一种优良的细化变质方法。     

GIS铝合金罐体的铸造技术

本文就铝合金罐体的主要铸造方法(即砂型铸造、砂型低压铸造、金属型砂芯低压铸造、金属型低压铸造和V法铸造)所涉及的设备、模具和工艺方面的技术要点进行分析和探讨。     

快速凝固/粉末冶金工艺制备阻尼铝合金的组织与性能

采用快速凝固/粉末冶金法（RS P/M）制备Al-9.0?-1.9%Mo-1.6%Si（FMS0918）合金及FMS0918/5%（Zn-30%Al）金属/金属复合材料挤压棒材,观察其组织并测试了其室温拉伸性能、阻尼性能和密度.结果发现：两种材料都具有良好的拉伸性能和阻尼性能.和FMS0918合金相比,FMS0918/5%（Zn-30%Al）合金的强度有所提高,塑性降低,但两者差别不大;加入Zn-30%Al粉末后,阻尼性能有明显改善,在100℃以下是基体合金的2倍;两种材料的密度均小于3.1g/cm^3.     

钛合金显微组织与性能定量关系的模型

提出利用软计算方法定量分析钛合金显微组织与性能的关系。在实现钛合金显微组织的定量分析和参数化表征的基础上,探讨以钛合金显微组织特征参数为输入变量、以性能为预测输出变量的组织与性能定量关系模型的构建方法。依据长期实践中得到的组织影响性能的定性规律及热加工工艺对组织特征的影响程度,提出定量关系模型显微组织信息预处理过程中组织特征参数评价取舍原则。运用人工神经网络建立Ti-17合金组织与室温拉伸力学性能的定量关系模型,研究建模的具体方法。该模型对各项性能指标具有较高的预测精度,说明提出的建模思想合理和模型构建方法可行     

Pitting Potentials of Aluminium Alloys

The pitting potential of the following aluminum alloys in 3% sodium chloride solution was measured using potentiodynamic and potentionstatic methods: Al-2.7 Mg with 0–0.47% Cr, Al-2.7 Mg with 0–0.94% Mn, Al-2.7 Mg-0.43 Mn with 0–0.31% Cr, Al-4.7 Mg-0.13 Cr-0.78 Mn, Al-51 Mg with 0.1 and 0.3% Sb, Al 2S-1/2H (commercial aluminum) super pure Al (99,99% Al). The results show that the pitting potential is not much affected by the alloying elements. The pitting potetial decreases with increasing content of magnesium and increases slightly with increasing content of manganese up to a certain point. The nature and amount of secondary phases do not seem to have any marked influence upon the pitting potential.     

Hot-tearing in Aluminium Copper Alloys

An experimental technique has been developed to investigate hot tearing. In this technique either the load or strain built up during casting could be measured as a function of the mould wall temperature. Experiments were carried out in Al—Cu alloys. Although there was considerable scatter in the results, it was concluded that strength began to build up in the casting when either the liquid volume fraction reached about 4% or when the eutectic temperature was reached. It was also concluded that the initial crack or hot tear occurred in a thin film of liquid or in the solid just below the eutectic temperature. It is suggested that the crack occurs in the liquid when the alloy composition is less than the most susceptible hot tearing composition and in the solid for higher compositions. The crack occurs in the liquid when the liquid volume fraction reaches about 2%. A numerical analysis was made of the heat flow in the casting so that corrections could be made to the thermocouple readings and a technique was developed to calculate the heat transfer coefficient from temperatures measured near the mould wall.     

Corrosion Inhibitors for Aluminium Alloys

Data (including literature data) are presented on the inhibition of the corrosion of Al and some Al alloys in hydrochloride, sulfuric, acetic and oxalic acids and sodium hydroxides. In this context the influence is shown of parameters such as inhibitors structure and concentration, temperature, time, medium concentration and external currents. Inhibitors dealt with include aliphatic and aromatic amines, carbonyl compounds (aldehydes, ketones); in this context it is shown that functional groups and their relative positions may have an important effect on inhibitor efficiencies.     

镁合金铸造技术进展

综述了近年来国外在镁合金熔炼气体保护方法、熔炼炉设计和铸造工艺方法方面的最新研究成果。     

合金元素及制备工艺对1XXX系铝合金组织及性能的影响

通过直接激冷铸造（DCC）与双辊铸轧（TRC）方法生产了具有不同Fe、Si、Cu和Mn含量的1XXX系铝合金坯料,随后通过均匀化、热轧、冷轧和退火等加工工艺制备了厚度为13 μm的铝箔。结果显示,铸造工艺对铝箔强度影响较小,双辊铸轧引入的较细第二相有利于铝箔塑性。在580 ℃以上进行均匀化处理可细化直接激冷铸造铸锭的粗大晶界金属间化合物,并使其在后续热轧中破碎为小颗粒。因Cu溶质原子可提高加工硬化速率,添加Cu元素的效果优于添加Fe、Si和Mn元素。中间退火时铝箔厚度对力学性能有显著影响,这和厚度与晶粒尺寸之间的比值有关。室温储存会导致较薄铝箔的力学性能下降,这与大应变后发生的回复机制有关。     

Fretting Corrosion Products of Aluminium Alloys

Abstract

An examination of a black powder produced by the fretting of aluminium alloy surfaces in a ship's hold has been carried out.

The fire risk associated with the accumulation of this type of material in confined spaces has been considered.     

高强度铸造铝合金凝固过程中的元素偏析

通过液淬的方法，研究Al-4.5Cu合金及添加Si,Mn,Ni,Zr元素后合金的凝固过程及溶质分布。结果表明，将Si,Mn,Ni,Zr元素的加入，都能使Al-Cu合金的结晶温度间隔不同程度地减少，其中Al4.5Cu3Si的结晶温度间隔最小，Cu的分布,特点是：晶界高于晶内，一次晶界高于二次晶界”，并随着温度的降低Cu向晶界偏析的趋势加剧，Ni的分布，晶界高于晶内，Mn的分布，晶界高于晶内，但差别不大，Zr在晶界与枝晶间的偏析处的含量较高。     

Quantitative Electron Tomography for Accurate Measurement of Precipitates Microstructure Parameters in Al–Cu–Li Alloys

Mechanical theories show that properties of alloys are strongly dependent on the morphological parameters oftheir strengthening precipitates.However,accurate measurement of precipitates microstructure parameters is still a challenging task.In this article,we develop a quantitative electron tomography method by combining computer vision technology to accurately characterize the three-dimensional microstructure parameters,such as volume fractions,sizes and distributions,of the T₁ and δ’...     

气压渗流铸造泡沫铝的试验研究

采用自制的气压渗流铸造试验装置和正交试验方法,探索了粒子层的预热温度,铝液的浇注温度、充型压力、充压保持时间以及粒子粒度等工艺因素对铝液渗透深度与铸件有效高度的影响,并对试验装置结构上的有关问题进行了分析讨论,为泡沫铝的渗流铸造提供参考。     

Microstructure of Iron-Sulfur Alloys

The distribution of sulfur in iron was found to be dependent upon the time and temperature of the treatment as well as the chemical composition of the sulfide. With higher temperatures, the sulfide phase spreads more extensively between the iron grains. A complete network, however, does not form until approximately 1300°C (2372°F), at which temperature the dihedral angle approaches zero. Silicon has little effect on this change. Aluminum, oxygen, and manganese all modify the temperature of sulfide network formation to a higher value. The microstructures which result and have significance in relation to hot-shortness are discussed.     

Na、Ca元素在铝及铝合金中的处理技术

根据精炼介质和反应类型不同,铝及铝合金中Na、Ca杂质的处理技术可分为氯化处理、电化学冶金、真空处理和加入反应性熔剂等方法。分析和讨论了各种铝及铝合金中Na、Ca杂质处理技术的反应机理、应用特点和局限性,并对发展趋势进行了展望。     

Na、Ca元素在铝及铝合金中的危害作用

分析了铝及铝合金中Na、Ca杂质的生成过程和相关机理,论述了Na、Ca杂质的主要来源途径及其对铝及铝合金的危害作用。分析和论述的结果表明,Na、Ca杂质主要是在冶金过程中产生并污染电解铝液,进而对铝合金的铸造性能和产品质量产生重要的影响。