J.Chen
,
Y.X.Wang
,
W.P.Dong
,
X.Y.Ruan
金属学报(英文版)
Based on the characteristics of 3D bulk forming process, the arbitrary Lagrangian-Eulerian (ALE)formulation-based FEM is studied, and a prediction-correction ALE-based FEM is proposed which integrates the advantages of precisely predicting the boundary configuration of the deformed material, and of efficiently avoiding hexahedron remeshing processes. The key idea of the prediction-correction ALE FEM is elaborated in detail. Accordingly, the strategy of mesh quality control, one of the key enabling techniques for the 3D bulk forming process numerical simulation by the prediction-correction ALE FEM is carefully investigated, and the algorithm for hexahedral element refinement is formulated based on the mesh distortion energy.
关键词:
prediction-correction ALE FEM
,
null
,
null
Materials Characterization
This paper describes work performed to determine some of the properties of the electroless Ni-W-P amorphous deposits. Phosphorus contents were varied up to 32 at.%, and the amorphous structure was found to be present at phosphorus contents above 5 at.%. Irrespective of P content, all the deposits exhibited excellent adhesion to metallic substrates. The addition of even small amounts of W provided greatly increased hardness compared with the plain Ni-P deposits. The wettability properties of the Ni-W-P deposits were found to be comparable to those of Ni-P and N-B-P deposits but inferior to those of Ni-B deposits. (C) Elsevier Science Inc., 1996
关键词:
nickel
胡光辉
,
杨防祖
,
王森林
,
吴辉煌
材料保护
doi:10.3969/j.issn.1001-1560.2003.06.005
测量了化学镀Ni-P和Ni-W-P过程混合电位随时间的变化,并分析其变化规律.指出Emix的正移与pH值随时间而降低有关,而且pH值的降低会加速化学镀的诱发过程.低碳钢诱发化学镀Ni-W-P会在混合电位-时间曲线上出现两个电位阶梯,其原因在于低碳钢在给定的镀液体系中稳定电位不够负,不能提供足够的能量使化学镀Ni-W-P快速发生,只有当表面形成达到一定覆盖度的具有催化活性的Ni原子层后,才能迅速地诱发化学镀过程;而Ni-P和Ni-W-P的稳定电位足够负,可以使化学镀过程快速诱发,故仅有一个电位阶梯.
关键词:
化学镀
,
Ni-P
,
Ni-W-P
,
混合电位
郑明新
,
朱永华
,
张翔
材料研究学报
本文中提出了一种可获得非晶态镀层的Co-W-P 合金电刷镀液。试验表明,Co-W-P 镀层从大约350℃起发生晶化,并同时发生Co_2P 的沉淀析出过程,产生二次硬化效应,而使红硬性提高。将这种镀层应用于热模具,可提高模具使用寿命50—200%;应用于冷模具时,也能使寿命大幅度提高。所以,非晶态Co-W-P 合金镀层的刷镀技术,是一种可提高模具寿命的新的表面强化处理方法。
关键词:
GUO Zhongcheng
,
LIU Hongkang
,
WANG Zhiyin
,
WANG Min(Department of Metallurgy
,
Kunming institute of Technology
,
Kunming 650093
,
China) Manuscript received 8 May 1995
金属学报(英文版)
The Effects of heat treatment temperature on the hardness,wear resistance and structure of the amorphous Ni-W-P-SiC composite coatings have been investigated.The results show that Ni-W-P-SiC composite coatings are amorphous under 300℃, partially crystalline at 300-400℃,and crystalline when heat treatment temperature reaches 400℃,the crystals being fine Ni3P phase particles.The hardness,wear resistance and the crystallization temperature of the composite coatings increase when an additive is added into the bath.The hardness and wear resistance of the coatings increase with increasing heat treatment temperature,and they will reach their peak values when the heat treatment temperature reaches 400℃.Corrosion experiment indicates that the corrosion resistance of amorphous Ni-W-P-SiC composite coatings in various kinds of corrosive media except nitric acid is better than that of stainless steel 1Cr18Ni9Ti.Scanning electron microscopy observation shows that the additive has no effect on the surface appearance of the coatings,but the current density and the pH value have considerable effects on the surface appearance.
关键词:
:electrodeposition
,
null
,
null
王羽
,
林利平
,
王安军
,
庞建飞
钢铁研究
武钢炼钢总厂二分厂对高磷钢冶炼工艺进行优化,通过转炉脱磷原理分析,减少熔剂加入量,降低终渣碱度和w(FeO),达到高磷出钢降低成本的目的,平均出钢w(P)达0.044％,熔剂、合金消耗大幅度降低.
关键词:
高磷钢
,
碱度
,
消耗
,
终点w(P)
梁琨
,
于媛
,
牛立斌
,
许建军
电镀与涂饰
doi:10.3969/j.issn.1004-227X.2007.03.002
通过对Ni-W-P合金镀层在低温热处理前后的XRD和SEM检测得知,无论镀态还是热处理态,镀层结构均为非晶态,晶粒均匀,晶界清楚,并且热处理后晶粒长大.在硫酸和盐酸介质中的耐蚀性测试表明,除了低体积分数(5%左右)和高体积分数(20%左右)盐酸之外,热处理态的耐蚀性均高于镀态的耐蚀性.通过析氢性能测试,得知镍基合金的电催化活性依次为Ni-W-P＞Ni-P＞Ni-W＞Ni.
关键词:
Ni-W-P合金镀层
,
热处理
,
非晶态
,
耐蚀性
涂抚洲
,
蒋汉瀛
材料保护
doi:10.3969/j.issn.1001-1560.1999.10.006
研究发现,非晶态Ni-P合金电镀体系中加入少量Fe,W等元素对镀层性能有影响,非晶态Ni-P镀层中引入少量Fe,W元素既能保护镀层优良的耐蚀性又可大大提高其硬度和耐磨性.
关键词:
Ni-Fe-P合金
,
Ni-W-P合金
,
电镀
,
非晶态
,
硬度
,
耐蚀性
刘殿龙
,
杨志刚
,
刘璐
,
张弛
稀有金属材料与工程
采用直流电沉积法,在低碳钢表面成功沉积Ni-W-P镀层.应用X射线荧光(XRF)、扫描电子显微镜(SEM)、俄歇电子能谱(AES)、X射线衍射(XRD)仪等方法,研究电流密度、镀液pH值和镀液温度对Ni-W-P镀层成分、表面形貌和结构的影响.结果表明,电流密度和镀液pH值的变化对Ni-W-P镀层成分的影响很大,而电流密度、镀液pH值和温度对镀层厚度的影响较小.电流效率随着电流密度和镀液温度的增大分别降低和升高,而随着镀液pH值的变化,在pH=7.0时有极大值.镀液pH值对Ni-W-P镀层结构有较大影响,在pH=8.0时,镀层呈现明显的Ni(111)峰,此时镀层硬度达到极大值7130 MPa.在此基础上,对Ni-W-P镀层的电沉积机制做了进一步探讨.
关键词:
Ni-W-P镀层
,
电流密度
,
pH值
,
镀液温度
