阻燃剂BDP的合成及应用研究

提出了以三氯氧磷、双酚A和苯酚为原料合成阻燃剂四溴双酚A磷酸酯齐聚物（BDP）的路线。研究了催化剂的选取以及原料配比、反应温度、反应时间等因素对反应收率的影响,确定了最佳的工艺条件：三氯化铝的催化效果最好,用量为双酚A的1．5％;三氯氧磷、双酚A和苯酚的摩尔比为6：1：4．02;酰氯化反应温度为40-45℃反应4h,80～85℃反应6h;酯化反应温度140～150℃。反应时间8h,产品收率为86％。用于PC／ABS合金显示良好的阻燃效果。     

微量元素对钛硅共晶合金压缩性能的改善

研究了钇、铍、钐、硼、钕等微量元素对Ti-8.5%Si(质量分数)共晶合金微观组织和室温压缩性能的影响。试验表明,添加适量钇、铍、钐、硼、钕等元素,均可有效提高Ti-8.5%Si合金的室温压缩强度和塑性,并细化其微观组织。其中,硼对Ti-8.5%Si合金室温压缩塑性的改善最为显著。分析认为,硼很可能以异质形核质点的形式,提高合金的形核率,从而细化合金的微观组织,改善合金的室温塑性。     

Image segmentation of small defects in precision weldments with complex structure

In this paper, the X-ray nondestructive test method of small defects in precision weldments with complex structure was presented. To resolve the difficulty of defect segmentation in variable grey image, the image processing based on Visual Basic programming method was adopted. The methods of automatic contrast and partial grey stretch were used to enhance the X-ray detection image which has relatively low contrast, then automatic threshold method was carried out to segment the two high intensity zones, and weld zones which contain the small defects was extracted. Smoothing and sharpen processing were proceeded on the extracted weld zones, and small defects in X-ray detection image of weldments with complex structure were segmented by using the method of background subtraction in the end. The effects of raster were eliminated, and because of that the image processing was only proceeded on the extracted weld zones, the calculated speed using the above provided algorithm was improved.     

Principles and application of RES welding technology

Friction element welding technology is rich of flow drill screws combined with friction welding technology and is developed for the hot-forming steel plate and aluminum alloy welding of car body-in-white. In this paper, the principle of RES welding technology, equipment, technical characteristics, application condition and welding parameters are analyzed systematically. Moreover, the changing laws of welding parameters and welded joint quality control standards are described, which provides the necessary technical support for safety and light-weight car body design requirements. This study has high practical application value, and enriches the automobile body joining technology.     

热处理温度对超级双相钢UNS S32760管材组织性能的影响

采用6 300 t卧式挤压机生产超级双相钢UNS S32760无缝钢管,以不同温度对管材进行固溶处理,研究固溶温度对管材金相组织、力学性能和腐蚀性能的影响。结果表明:随着固溶温度的升高,UNS S32760铁素体相(α相)含量逐渐增多,奥氏体相(γ相)含量逐渐降低,抗拉强度、伸长率基本保持不变,屈服强度逐渐升高,冲击功整体呈上升趋势;在固溶温度1 100℃时,管材组织中α相和γ相比例约为1∶1,点腐蚀速率最低,耐点蚀性能最优,腐蚀速率为0.031 mm/a。     

冷却速度对675装甲钢显微组织的影响

利用差分膨胀仪、金相及透射电镜研究了675装甲钢过冷奥氏体在不同冷却速度下的相变过程及产物.结果表明,冷却速度在3℃/min～2000℃/min范围内,随冷速的增大,675装甲钢中发生的组织转变变化很大,相变产物依次出现粒状贝氏体(粒B)、上贝氏体(上B)、下贝氏体(下B)以及片状和板条混合马氏体(M).此外,675装甲钢具有相当好的淬透性,临界淬火速度为25℃/min,Ms点为320℃.     

如何延长柴油机的使用寿命

柴油车具有热效率高、燃料使用经济陛能好、功率范围宽、故障少等优点，所以我国大、中吨位的载重车、工程机械等设备几乎全部采用柴油车。柴油车由于使用和维护不当而造成过早损坏，影响了经济效益。作为汽车驾驶员，应当掌握一些柴油机的使用及维护知识，以便更好地发挥柴油机的动力性，延长其使用寿命。柴油机的使用寿命一般取决于柴油机气缸套和曲轴磨损到极限尺寸的时间。     

现代工业培训与专业教育相结合探讨

以数控加工为代表的现代工业培训是金工教学的发展潮流。本文探讨了以兴办专业为形式的深化现代工业培训的教育改革研究。研究表明这是培养应用型人才和搞活金工教学的有效途径，是深化现代工业培训的重要组成部分。     

Evaluation of TiAI and 40Cr diffusion bonding quality using ultrasonic reflection spectrum

Combined with ultrasonic pulse-echo technique, reflection spectrum analysis was introduced to evaluate TiAl and 40Cr diffusion bonding quality. Frequency dependence of reflection coefficient was used to distinguish perfect bonding from imperfect bonding. It is found that the reflection coefficient from perfect bonding interface does not vary with frequency. When the size of imperfections is much smaller than the wavelength of ultrasound, the reflection coeffwient depends on frequency. When the size of imperfections is the same order of or even larger than the wavelength of ultrasound, the reflection coeffwient does not exhibit frequency dependence. However the amplitude of imperfect interface is higher than the amplitude of perfect bonding interface. A combination of reflection spectrum analysis and ultrasonic pulse-echo technique provides more accurate information about the bonding quality of dissimilar materials.     

冷却速度对675装甲钢显微组织的影响

利用差分膨胀仪、金相及透射电镜研究了675装甲钢过冷奥氏体在不同冷却速度下的相变过程及产物。结果表明，冷却速度在3℃／min-2000℃／min范围内，随冷速的增大，675装甲钢中发生的组织转变变化很大，相变产物依次蹦现粒状贝氏体（粒B）、上贝氏体（上B）、下贝氏体（下B）以及片状和板条混合马氏体（M）。此外，675装甲钢具有相当好的淬透性，临界淬火速度为25℃／min，Ms点为320℃。