H.Y.Gao
,
Q.Sun
金属学报(英文版)
The paper deals with different plastic deformation behavior of electroformed copper liner of shaped charge,depormed at high strain rate(about 1×10^7s^-1) and normal strain rate (4×10^-4s^-1).The crystallographic orientation distribution of grains in recovered slugs which had undergone high-strain-rate plastic deformation during ex-plosive detonation was investigated by electron backscattering Kikuchi pattern tech-nique.Cellualar structures formed by tangled disocations and sub-grain boundaries consisting of dislocation arrays were detected in the recovered slugs.Some twins and slip dislocations were observed in specimen deformed at normal strain rate.It was found that dynamic recovery and recrystallization take place during high-strain-rate deformation due to the temperature rising,whereas the conventional slip mechanism operates during deformation at normal strain rate.
关键词:
electroformation
,
null
A.L. Fan
,
W.H. Tian
,
Q. Sun
,
B.S. Wang
金属学报(英文版)
The microstructures of electroformed copper liners of shaped charges that had undergone high-strain-rate deformation were observed by optical microscopy (OM) and scanning electron microscopy (SEM). Meanwhile, the orientation distribution of the grains in the recovered jet was examined by electron backscattering Kikuchi pattern (EBSP) technique. EBSP analysis reveals that the fibrous texture observed in the as-electroformed copper liners disappeared after explosive detonation deformation. OM observation shows that the microstructure evolves systematically from the jet center to its perimeter during cooling from high temperatures after explosive detonation deformation. This microstructural characteristic is similar to that of solidification, i.e. there exist equiaxed grains in the center of the jet and significant columnar grains around the equiaxed grains. The result reveals that there is melting-related phenomenon in the jet center. Corresponding microhardness variations from the jet center to its perimeter is also determined. All the phenomena can be explained by a strong gradient of temperature across the section of the jet during plastic deformation at high-strain-rate.
关键词:
jetting
,
null
,
null
李春华
,
成生伟
,
王雷
,
杨峰
,
田文怀
兵器材料科学与工程
doi:10.3969/j.issn.1004-244X.2009.06.003
采用直流电铸法在氨基磺酸盐铸液中电铸制备镍药型罩,利用光学显微镜(OM)、X射线衍射仪(XRD)和背散射电子衍射(EBSD)技术对其组织结构进行观察和分析.研究结果表明:所制备药型罩表面质量良好,由于电铸过程中添加剂的不断消耗,从药型罩的内表面到外表面存在微观组织的不均匀性,晶粒沿平行于罩壁的法线方向呈柱状生长,在罩壁的法线方向存在<100>丝织构.
关键词:
氨基磺酸盐
,
电铸
,
药型罩
,
镍
王雷
,
李春华
,
成生伟
,
田文怀
,
贾成厂
兵器材料科学与工程
doi:10.3969/j.issn.1004-244X.2010.02.011
利用脉冲电铸法制备纯镍药型罩,研究脉冲参数对电铸镍微观组织和性能的影响规律.实验采用两种不同的电铸液配方,分别改变脉冲电源的占空比、频率、阴极电流密度,得出电铸镍硬度随电铸参数的变化规律.研究结果表明,在单向脉冲电铸条件下,增大正向电流的占空比能够使得电铸镍的硬度变小.在双向脉冲电铸条件下,连续增加正向电流的占空比可使得电铸镍的硬度先增大后减小.当占空比达到50%左右时,电铸镍的硬度达到最大值;频率增加使得电铸镍的硬度先缓慢增加,当频率增加到4 000 Hz以上时,电铸镍的硬度快速增加.随着阴极电流密度增加电铸镍的硬度会变小.与此同时,利用脉冲电流可以得到晶粒细小,晶粒形态为等轴晶的电铸镍.
关键词:
电铸
,
镍药型罩
,
电铸镍
,
脉冲电铸
段凯歌
,
徐国跃
,
乔加亮
,
张伟刚
,
丁儒雅
兵器材料科学与工程
采用电铸法制备镍药型罩,利用X射线衍射仪、扫描电镜研究电铸镍药型罩的微观组织,通过拉伸试验研究电铸镍药型罩的力学特性.结果表明:在无添加剂时,随着电流密度的增大,晶粒尺寸变大;加入添加剂后,晶粒细化,可得到超细晶镍药型罩.脉冲电铸制备的药型罩表面光滑,晶粒尺寸约为500 nm.电铸镍药型罩中存在强烈的<100>丝织构,电铸参数的改变对镍药型罩织构影响较小.力学特性研究表明其屈服强度为256 MPa,伸长率可达7.4%.断口形貌观察发现电铸超细晶镍的断裂属于延性断裂.
关键词:
电铸
,
药形罩
,
镍
,
微观组织
