热处理工艺对车用减震板组织和性能的影响

通过对不同热处理和时效处理工艺的Mn-Cu合金的X射线分析、微观组织分析和阻尼性能测试,分析了热处理冷却方式、时效处理时间对合金组织和阻尼性能的影响。研究表明,时效处理不会产生新相,随着时效处理时间的增加,晶粒尺寸增大,阻尼性能提高,但超过一定时间,阻尼性能反而降低,其中时效处理8 h能够获得最佳的阻尼性能。     

The Kinetics of Hydrogen Diffusion in Ti_3Al-Based Alloy

lIntroductionAIloysbasedOI1inter111etanicsTi3AlI1avebee11stndied..inconsiderabledetaiIinrecentvearsI"'1.Theyarelegiti111ateca11didaten1ateriajsforaerospaccsysten1s,suCI1asenginesa11dairti-al11esofahydrogen-burl1ingpropulsion'syste111.Tl1erefore,theinterac…     

非晶、纳米晶铁基合金的实验研究

用X射线衍射分析仪(XRD), 透射电子显微镜(TEM), 扫描电子显微镜(SEM)和X射线吸收精细结构分析仪(EXAFS)对机械合金化后的FeNiPB(Cu, Nb)混合粉末进行了分析研究. 研究结果表明: FeNiPB(Cu, Nb)混合粉末球磨20h后合金化, 球磨80h后FeNiPB(Cu, Nb)混合粉末中的Fe, Ni原子处于非晶环境中, 粉末的形态为棉絮状, 电子衍射为典型的非晶环. XRD, EXAFS, TEM的分析结果表明在该条件下, FeNiPB(Cu, Nb)混合粉末完全转变成了非晶. FeNiPB(Cu, Nb)非晶合金在520℃加热1h后产生纳米晶, 所以纳米晶铁基合金可通过FeNiPB(Cu, Nb)非晶合金部分晶化获得.     

La部分取代MI混合稀土贮氢合金的电化学性能

金属La部分取代MI（混合稀土）的贮氢合金电极Ml0.8La0.2Ni4.0Mn0.4Co0.4Al0.1（A）容易活化，其充电效率、放电容量、快速放电能力以及荷电保持能力比电极MlNi4.0Mn0.4Co0.4Al0.1（B）分别提高5．5％、7．0％、4．0％和8．2％。电极A放电过电位比电极增大，且循环稳定性下降。     

螺旋支架治疗前列腺增生的适应症探讨

自1992年6月至1994年10月,收治了10例记忆金属螺旋支架管治疗前列腺增生所致排尿困难的患者.采用耻骨上经膀胱开放手术,取出金属螺旋支架管,摘出前列腺。分析了10例置管失败的原因。就金属螺旋支架管治疗前列腺增生的作用、适应症进行了探讨,认为合并膀胱颈部纤维化、前列腺中叶增生及以纤维组织增生为主的良性前列腺增生者不适宜这种治疗。     

硼酸铝晶须的自诱导合成与表征

以纤维状的碱式碳酸铵铝(AACH)和硼酸为原料,在150℃左右发生低热固相反应,得到铝氧骨架上含有部分硼酸基团的纤维状中间体,接着在助熔剂硫酸钾的存在下将中间体在1100℃焙烧4h,得到反应混合物,用热水洗去该混合物中的可溶性助熔剂,烘干后得到产物。经XRD及SEM表征,证实该产物为直径分布均匀的硼酸铝晶须,晶须的平均直径为0．3um长度平均为15um．鉴于AACH在较低温度分解得到活性氧化铝时还保持着纤维状的形状以及这一温度硼酸基已接到铝氧骨架上的事实,初步提出了原位诱导合成硼酸铝晶须的生长机理。     

Preparation of AlN thin films for film bulk acoustic resonator application by radio frequency sputtering

Aluminum nitride （AlN） thin films with high c-axis orientation have been prepared on a glass substrate with an Al bottom electrode by radio frequency （RF） reactive magnetron sputtering. Based on the analysis of Berg＇s hysteresis model, the improved sputtering system is realized without a hysteresis effect. A new control method for rapidly depositing highly c-axis oriented AlN thin films is proposed. The N2 concentration could be controlled by observing the changes in cathode voltage, to realize the optimum processing condition where the target could be fixed stably in the transition region, and both stoichiometric film composition and a high deposition rate could be obtained. Under a 500 W RF power of a target with a 6 cm diameter, a substrate temperature of 450 ℃, a target-substrate distance of 60 mm and a N2 concentration of 25%, AlN thin film with preferential （002） orientation was deposited at 2.3 μm/h which is a much higher rate than previously achieved. Through X-ray diffraction （XRD） analysis, the full width at half maximum （FWHM） of AlN （002） was shown to be about 0.28°, which shows the good crystallinity and crystal orientation of AlN thin film. With other parameters held constant, any increase or decrease in N2 concentration results in an increase in the FWHM of AlN.     

Morphology evolution of two-phase Cu-Ag alloys under different conditions

Cu-Ag filamentary microcomposites with different Ag contents were prepared by cold drawing and intermediate heat treatments. The microstructure characterization and filamentary distribution were observed for two-phase alloys under different conditions. The effect of heavy drawing strain on the microstructure evolution of Cu-Ag alloys was investigated. The results show that the microstructure components consist of Cu dendrites, eutectic colonies and secondary Ag precipitates in the alloys containing 6%-24% （mass fraction） Ag. With the increase in Ag content, the eutectic colonies in the microstructure increase and gradually change into a continuous net-like distribution. The Cu dendrites, eutectic colonies and secondary Ag precipitates are elongated in an axial direction and developed into the composite filamentary structure during cold drawing deformation. The eutectic colonies tend to evolve into filamentary bundles. The filamentary diameters decrease with the increase in drawing strain degree for the two-phase alloys, in particular for the alloys with low Ag content. The reduction in filamentary diameters becomes slow once the drawing strain has exceeded a certain level.     

轴瓦的合理浇注及废品分析

详细介绍了轴瓦浇注的过程、废品产生的原因及有效防止缺陷的方法,从实践出发,对轴瓦的浇注工艺做了详细论述.     

Study on Moving Principle of Colonoscopic Robot

The moving principle of a colonoscopic robot is presented in this paper.The robot mainly consists of soft mobile mechanism for earthworm locomotion and turning mechanism based on shape memory effect.The soft mobile mechanism contacts colon wall with air-in inflatable balloons.so the robot has better soft and non-invasive properties.The turning mechanism can be actively bent by shape memory alloy components.It ensures the robot to adapt to the tortuous shape of colon.Therefore,the colonoscopic robot has good safety,lower working strength of surgeon and higher efficiency of colonooscopy.