钨系延期药预点火反应机理研究

通过程控升温模拟点火条件，根据ＤＳＣ图谱分析，找出主要反应区的温度范围。研究结果表明，钨系延期药预点火反应是一个真正的固－固反应。     

TiB2和SiCW对Al2O3陶瓷材料高温摩擦磨损特性的影响

研究了Ａｌ２Ｏ３、Ａｌ２ｏ３／ＴｉＢ２和Ａｌ２Ｏ３／ＴｉＢ２／ＳｉＣＷ三处陶瓷材料在不同条件下的擦靡损特性。结果表明：三种陶瓷材料与硬质合金摩擦副的摩擦系数随温度温度的增加有不同的变化规律，摩擦表面的Ｘ射线衍射分析表明，摩擦系数的变化与陶瓷物膜的和结构有关，在高温下Ａｌ２Ｏ３／ＴｉＢ２陶瓷材料摩擦表面形成了具有优良的高温润性的ＴｉＯ２氧化膜，因而ＴｉＢ２的加入明显改善了Ａｌ２Ｏ３陶瓷材料 摩擦磨损     

涂层材料的断裂分析(英文)

和基体厚度相比,涂层很薄,因此细观力学模型可把基体作为半无限弹性体。由于涂层和基体材料的膨胀系数及弹性系数不匹配,涂层材料中残余热应力的解析解为 E_c/(1-γ_c)·(α_s-α_c)△T。用有限元法校核,该应力和解析解吻合得好。通过对涂层产生裂纹驱动力和断裂韧性的讨论,提出了抗裂涂层厚度公式。     

稀土Si_3N_4陶瓷材料中铝的络合滴定法测定

提出了强碱介质沉淀钇及有关杂质元素而与铝进行分离的方法。试液酸化后采用ＮａＦ析出法络合滴定测定铝。     

化学镀SiCp／Ni－P复合镀层与基体结合强度及其影响因素

论述了ＳｉＣｐ／Ｎｉ－Ｐ复合镀层与钢基体的结合强度及其影响因素。复合镀层中离界面５μｍ厚度以内区域的组成及应力状态对镀层／基体的界面结合有决定性作用，在该区域以外ＳｉＣ粒径变化不影响镀层的结合强度。适当的热处理可提高界面结合力。     

一种碳－碳复合材料长寿命防氧化涂层的失效机制

用液相法联合ＣＶＤ法和硅化法制备了一种碳－碳复合材料复合梯度涂层，在此基础上对这种涂层在氧化过程中的失效机制进行了研究．结果表明：氧化层与液相层界面反应生成的气相产物是涂层失效的根本原因界面上气泡的不均匀形核、长大和破裂导致涂层表面出现孔洞．孔洞处气泡优先形核、长大和破裂并发展成为缺陷而使涂层失效     

Early detection of ageing in solder joints through laser probe thermal analysis of the peltier effect

We have recently developed an optical contactless method for testing the quality of solder joints during accelerated thermal cycling ageing processes.¹ The method was based upon the measurement of the dynamic thermal behaviour of the joint to short bursts of Joule heating. It has proved to be efficient in revealing the formation of cracks at the lead-solder interface. We present a method to evaluate ageing at a much earlier stage in the cycling process. We have observed in earlier work,¹ that before cracks appear, structural changes occur in the solder at the lead-solder interface. The thermal response of the solder joint is recorded over time to a Peltier heat perturbation produced by flowing a current pulse through the interface where structural changes occur. The key point in this method is to discriminate the Peltier effect from the Joule thermal response because both effects generate heat. The variation of the early Peltier response in the thermal cycling ageing tests is seen as a quantitative signature of the structural changes in the lead-solder interface.     

片式多层电容电阻复合元件的研制

采用低温共烧陶瓷(LTCC)技术将电容、电阻元件集成在多层陶瓷基板里,构成了一种新型的片式多层复合元件,并研究了其制造工艺性能和频率特性。结果表明,片式多层电容电阻复合元件制造工艺适合批量化生产,并为片式多层LC滤波器、LTCC基板及器件的研发提供了极好的参考价值。     

Optical measurements of thermal diffusivity of a material

The measurement of thermal diffusivity of a material (in particular, a thin film) is important for various reasons, e.g., to predict the heat transfer in the solid subjected to a thermal process, to monitor surface composition or morphology, or to detect invisible subsurface defects like delaminations. This measurement can be done in a noncontact manner using various photothermal methods. Such methods typically involve pulsed heating of the surface by small amounts using a laser source; the decay of the surface temperature after this pulsed photothermal heating is then probed to provide the thermal diffusivity. Various probing methods have been developed in the literature, including the probing of reflection, refraction, and diffraction from the pulsed heated area, infrared thermal radiometry, and surface deformation. This paper provides an overview of such techniques and some examples of their applications.     

n-Al2O3/Ni复合镀层的组织与滑动磨损性能研究

用电刷镀技术制得了镍基n-Al2O3复合镀层，并对镀层的滑动磨损性能进行了试验研究。纳米复合镀层的表面形貌比较细腻，镀层中纳米粒子分布均匀，与基质金属结合紧密。镀层显微硬度达到HV700，比快速镍镀层提高约40％。滑动磨损试验结果表明，随着纳米粒子含量的增大，镀层的耐磨性提高，摩擦系数也呈增大趋势；但当镀层中n-Al2O3粒子的超过2.56%(质量分数）时，镀层的耐磨性显著下降。纳米复合镀层的磨损机制以疲劳磨损为主，而快速镍底层以粘着磨损为主。