长效复合变质剂在铝活塞合金中的应用

通过检测活塞产品的金相组织、力学性能及台架试验指标,表明长效复合变质剂对ZL108和ZL109活塞合金变质效果优良、具有长效变质、无烟雾粉尘,改善劳动条件,降低生产成本等效果。     

TiC对新型Al-P中间合金变质效果的促进作用

本文研究了自制新型Al-P中间合金对共晶及过共晶Al-Si的变质作用。发现该Al-P中间合金对共晶及过共晶Al-Si合金都具有优良的变质效果。同时还发现，当铝合金熔体中存在TiC颗粒时，Al-P中间合金对两类Al-Si合金的变质效果会增强。当Al-24Si合金中TiC含量为0.03%时，初晶Si的平均尺寸由原来的47μm降为41μm，最大尺寸由原来的75μm降为55μm；加入Al-P中间合金和TiC颗粒后50分钟，就可以出现变质效果，时间再延长，变质效果也不会有更大的提高，当Al-12Si合金中TiC含量为0.03%时，初晶Si的平均尺寸幅度原来的50μm降为30μm,Al-P中间合金变质剂在铝合金活塞中有较好的应用。     

红梅-3号特种合金磷变质剂的研制与应用

为满足铝活塞产品质量的需要，继“红梅—1号多功能磷复合变质剂”和“红梅—2号磷酸盐块状变质剂”后，我们又新研制开发了多相长故、环保型“红梅—3号特种合金磷变质剂”。这是一种高技术合量的新型以—Si合金磷变质剂，无论在产品质量上、使用性能上还是变质效果可与国外生产的P——Cu棒变质剂媲美。     

浅析钙与钠对Al-Si合金磷变质效果的影响

本文简要介绍Al-Si合金磷变质工艺的发展概要;重点论述钙、钠两元素在Al-Si合金磷变质工艺中的作用及它们对磷变质效果的影响;同时介绍了不合格精炼剂、除渣剂等辅料对活塞铸造的危害.     

CX型锶盐长效复合变质剂在ZL104合金中的试验

作者研制的锶盐长效复合变质剂用于ZL104合金,对共晶硅的变质效果良好,提高了合金的力学性能。变质处理时,没有潜伏期,有效时间达7小时以上,对生产环境无污染。     

氢含量对Al-P中间合金变质效果的影响

利用测氢仪等测试手段研究了 ZL1 0 9熔体中氢含量对 Al- P中间合金变质效果的影响。结果表明 ,在相同的铸造条件下 ,变质后合金中熔体氢含量越高 ,初晶 Si晶粒的平均晶粒尺寸和最大晶粒尺寸越大。保温时间过长合金熔体有吸氢倾向 ,初晶 Si尺寸有增大趋势。在精炼处理充分的条件下 ,Al- P中间合金的变质效果可保持 3 0小时不失效     

Al-P中间合金的变质特性及变质机理探讨

通过在众多活塞厂家应用表明：A1-P中间合金无污染、无反应渣，变质效果好且稳定；节约能源，降低铝耗，综合成本低，克服了当前变质的缺点，有着广阔的应用前景。本文还探讨了A1-P中间合金的变质机理。     

铝硅活塞合金的组织细化浅析

1　前言为了提高铝活塞的高温机械性能 ,必须对共晶及过共晶的铝硅合金进行变质处理。目前 ,我国许多活塞厂家都已采用磷来细化初晶硅即可获得热膨胀系数低、尺寸稳定性高、导热性、耐磨性高抗腐蚀性好的优质活塞。现对目前活塞厂家通常采用的几种变质方法进行比较。2　几种变质方法优劣的比较对共晶组织有变质作用的元素有 Na、Ca、Ba、K、Sr、Sb、Te、Ti、Li以及稀土元素等。目前用于生产实际的变质元素有 Na、Sb和 Sr,对过共晶组织有变质作用的元素有 P、As和 S。1　Na变质处理钠是共晶类铝硅合金最常用的变质剂。钠的变质效果直…     

铝——硅共晶活塞合金的Na,P变质

本论文致力于KS1275活塞合金分别经Na,P变质后，在机械，物理性能以及铸造性能等方面的比较，同时基于铸造理论和实践结果，对影响P变质效果的一些重要因素进行分析，小结。     

Al—P中间合金对Al—Si合金的“绿色”变质

用 Al- 3P中间合金对 ZL1 0 9合金进行了变质生产试验 ,研究了其在生产中的工艺参数及加入工艺。对共晶成分的 Al- Si合金 ,其加入量按 W原料 × ( 0 .4%～ 0 .45 % ) + W回炉料 × 0 .1 %=WAl-3 P中间合金 进行计算称量 ,在 760～ 770℃变质即可取得良好的变质效果 ,生产出品质优良的活塞铸件。使用 Al- P中间合金变质剂加入方便 ,无渣无污染 ,可以提高合金的实收率、降低生产综合成本 ,适于工业化生产应用 ,是磷盐变质剂良好的替代品。     

A new idea for industrial safety in magnesium grinding: Suppression of hydrogen generation in wet dust collectors

Magnesium alloy waste dust particles will be generated during alloy grinding, which undergoes a hydrogen production reaction in wet dust removal systems and introduces the risk of hydrogen explosion. The inhibition of hydrogen evolution from waste ZK61 alloy dust by decyl glucoside (DG) and sodium tungstate (ST) in simulated industrial water was studied. The adsorption of a single inhibitor on ZK61 alloy dust exhibited inefficient inhibition. However, when DG and ST were combined, they synergistically inhibited hydrogen evolution, and the sustained-release rate reached 91.6%. The SEM, XRD, FT-IR and XPS results showed that a dense protective film composed of [DG-Mg] and MgWO₄ formed on the surface of the ZK61 particles. This film resulted from the synergistic inhibition of hydrogen evolution from ZK61 dust particles by DG and ST.     

"蓝箭"号机车传动齿轮箱螺栓断裂的原因分析及改进措施

由于铝合金齿轮箱和钢制螺栓的热膨胀系数不同,所以在齿轮箱温度升高后要产生附加的温差载荷。此温差载荷是螺栓失效的根本原因,由此依据相关公式提出了改进措施。通过对联接螺栓的受力分析,确定了螺栓受脉动载荷作用时的安全系数。原联接结构的安全系数不满足要求,改进后的安全系数满足要求。改进措施是有效的,且为以后齿轮箱的设计提供了参考。     

Experimental research on temperature rise and electric characteristics of aluminum air battery under open‐circuit condition for new energy vehicle

Due to lack of systematic research on open‐circuit voltage (OCV) and electrolyte temperature rise characteristics of aluminum air battery, in order to explore the influential factors on the OCV and electrolyte temperature rise of aluminum air battery, in this paper, for the first time, we studied the effects of different ambient temperature conditions, different concentrations of NaOH and KOH electrolyte, and pure aluminum and aluminum alloy on the OCV and electrolyte temperature rise of aluminum air battery. Results show that the OCV of aluminum air battery is obviously affected by ambient temperature conditions, electrolyte concentration, and different anode materials. The OCV range is 1.5 to 1.8 V at 0°C under different KOH‐electrolyte concentrations when aluminum alloy is used as anode material; with the increase of ambient temperature, the OCV will rise, and the range is 1.8 to 1.95 V. The working process of aluminum air battery is accompanied by the phenomenon of heat release, and the temperature rise range of electrolyte will not exceed 7°C when aluminum alloy is used as the anode material; however, the highest temperature of the electrolyte can reach 100°C when pure aluminum is used as the negative electrode material. The results of this study will provide theoretical guidance for designing aluminum air batteries and identifying their optimal operating conditions.     

Effect of electrolyte concentration on the electrochemical properties of an AB5-type alloy for Ni/MH batteries

This publication is the first of a series of three that we have undertaken to study the effect of electrolyte concentration on electrode performance. Here, the electrochemical properties of an AB₅-type alloy, namely LaNi_3.6Co_0.7Mn_0.4Al_0.3, are investigated using different KOH electrolyte concentrations (i.e. 2 M, 4 M, 6 M and 8 M). The next two publications will be concerned with an AB₂-type alloy and a Mg-based alloy, respectively.     

A similarity solution for solidification of an under-cooled binary alloy

A similarity solution for solidification of an under-cooled binary alloy melt in a semi-infinite, one-dimensional, insulated slot is developed. It is shown that this solution is a generalization of the known similarity solution for the solidification of an under-cooled pure melt, and is a special case of the similarity solution for solidification of a binary alloy previously presented in the literature. The new solution is used to quantify the effect of the Lewis number (ratio of thermal to solutal diffusivity) on the behavior of solidification. Limits on the amount of under-cooling that will admit a physically meaningful solution are obtained.     

Study on the influence of Mg content on the risk of hydrogen production from waste alloy dust in wet dust collector

We use a proprietary automatic Al–Mg alloy–water reaction test apparatus to compare the hydrogen evolution profiles of Al-xMg (x = 10%,20%) with different particle sizes, characterize the waste Al-xMg alloy dust particles before and after reaction through SEM, EDS, and XRD, and present a three-stage four-step hydrogen evolution model of Al-xMg (x ≤ 35%) alloy dust particles. It is discovered that the reaction of the Al–Mg alloy in water is a hydrogen evolution–adsorption–slow diffusion process. The particular β-Al₃Mg₂ in Al-xMg (x ≤ 35%) will adsorb the resulting hydrogen to form MgH⁺ and adhere to the surface of the particles. As the Mg content in the alloy increases, the hydrogen evolution reduces. The entire process lasts around 5–6 h, with maximum hydrogen conversion rate of 54% (Al–10%Mg, d (50) = 12 μm, α = 0.544). Our hydrogen evolution model provides very useful theoretical references for avoiding hydrogen explosion in Al–Mg alloy manufacturing facilities.     

Development of process for aluminising nickel alloy 718 strips for tube bundle support structures in liquid sodium–water steam generators

Abstract

The tubes in liquid sodium–water steam generators of the Indian prototype fast breeder reactor (PFBR) will be supported by corrugated nickel alloy 718 strips. Aluminisation of nickel alloy 718 strips has been chosen for this application because of the excellent performance of aluminide coatings in reducing impact fretting wear of the tubes due to flow induced vibrations and compatibility of the coating with liquid sodium at the operating temperature of the steam generators. Aluminisation of nickel alloy 718 strips for steam generator tube bundle support structures has been developed using a procedure involving thermal spraying of aluminium followed by diffusion heat treatment in vacuum atmosphere. One of the advantages of the technique is that it will coat only the desired surfaces of the strips, whereas in conventional pack cementation process, significant precautions have to be ensured. Furthermore, this process has enabled aluminisation to be carried out at a much lower cost than the conventional process of pack aluminising. The problems encountered during the initial trials and technology development, such as coating thickness and distortion, are discussed. A process flow chart for this procedure to take the job on an industrial scale is also reported. This process (under patenting) has been adopted for the aluminisation of corrugated strips for the support structures of one steam generator module and the steam generator for a test facility during the technology development phase, as also of all the steam generators being fabricated for the PFBR.     

高温热管工质的选择

高温热管是高温技术领域的一种高效传热设备。本文讨论高温热管工质的选择。首先介绍选择的准则，然后比较讨论了碱金属制品作为工质的某些特征，最后批出了钢－钾合金作为高温热管工质的优越性。     

浅谈P92材料的特点与市场概况

近年来,随着火电市场的大力发展,我国对于P92材料的应用,以四大管道和锅炉为主,日趋成熟,并且在P92材料的供应方面,成功打破了欧美日等国家垄断,实现了国产化。然而就全世界范围内而言,P92材料在国际市场的应用并不多,主要还是集中在中国市场。P92材料距离全世界的普遍推广还是有很长的一段路要走。     

低合金耐热钢预处理工艺的正交试验和回归分析

低合金耐热钢广泛应用于大功率汽轮机等发电设备中。但该钢在热加工过程中极易产生粗晶，从而影响性能。因此在长期的生产中．低合金耐热钢粗晶问题已成为该材料热处理返修的主要原因之一。在分析产生粗晶根源的前提下，本文通过6SIGMA管理方法，采用正交试验设计及回归分析工具，找出了该钢的最佳热处理工艺参数并制定了控制标准，使该钢因粗晶造成的热处理返工率显著下降，经济效益明显提高。