大规格爆炸钛/钢复合板力学性能及界面的研究

分别以3 mm×3 m×7 m的TA2板和9 mm×3.2 m×7.2 m的Q235钢板作为覆板和基板,使用四种不同成分的炸药制备了大规格TA2/Q235钛/钢爆炸复合板,并对复合板的剪切强度以及界面组织进行了研究。结果表明,炸药的爆速、猛度和做功能力随乳化炸药含量的增多而增大。经UT检测,使用4#炸药爆炸制备的钛/钢复合板结合率接近100%;平均剪切强度最高为278 MPa。爆炸钛/钢复合板都存在一定厚度的界面层,炸药做功能力越强,界面层厚度越薄。该试验所制备的钛/钢复合板界面层厚度最薄仅为1.1μm。爆炸钛/钢复合板界面层的形成是Ti和Fe元素互扩散的结果。扩散过程中,在高温的作用下,界面层中容易形成β-Ti、TiFe和TiFe2金属间化合物。     

真空轧制钛/钢复合板的组织与性能

钛/钢复合板兼具钢的良好力学性能及钛的优异耐腐蚀性,广泛应用于石油、化工、电力及海洋工程等领域。南钢采用真空轧制复合法制备的钛/钢复合板,不添加过渡层,其拉伸性能、弯曲性能及剪切强度等均满足标准要求,而且剪切强度平均在209 MPa左右,超过标准要求的140 MPa。钛/钢复合板的各项性能达到GB/T8547-2006标准R1类复合板的要求。     

钛/钢复合板及其制备应用研究现状与发展趋势

随着钛/钢复合板的应用领域不断拓展,市场对钛/钢复合板的尺寸和性能都提出了新的要求,现有的制备方法和工艺也面临着巨大挑战。本文从原材料情况、复合板尺寸、界面特征和力学性能等方面概述了钛/钢复合板研究现状,评述了钛/钢复合板目前的主要制备方法及其优缺点,综述了表面处理方法、热轧温度、过渡层金属和热处理工艺对钛/钢复合板界面结合质量的影响,阐述了钛/钢复合板的应用现状,指出了钛/钢复合板面临的主要问题及未来的重点研究方向。      

真空制坯热轧钛/钢复合板工艺及性能

钛/钢复合板的需求量日益增多，真空制坯热轧复合法（VRC）是制备高性能钛/钢复合板的有效工艺。介绍了钛/钢复合板制备工艺的国内外现状和工艺特点。依托863重点项目“钛/钢复合板研究与生产技术开发”和十三五重大课题“容器板轧制复合原理与关键技术”，利用真空制坯热轧复合法（VRC）在实验室和钢厂进行了一系列钛/钢复合板的轧制试验，对复合板的界面组织与力学性能进行了分析。实验室制备的钛/钢复合板，界面生成了明显的TiC层，未发现氧化物等杂质，断口有大量韧窝生成，复合界面平均拉剪强度达到了230MPa。钢厂试生产的钛/钢复合板，宽幅达到3500mm，界面生成连续的β- Ti层，拉剪断口未检测到氧化物，拉伸、冲击、弯曲等力学性能均满足国家标准，剪切强度均在196MPa以上，已达国内领先水平。     

爆炸焊接装药方式对钛/钢复合板组织及性能的影响

分别采用等厚度装药及分段装药两种不同的装药方式制备了钛/钢复合板,研究了金属复合板在爆炸焊接过程中爆炸压力分布及覆层金属变形规律,并对所制备的Gr1/Gr70爆炸复合板结合界面的微观组织特征和力学性能进行了分析。结果表明,采用分段装药工艺所制备的大面积钛/钢复合板界面无分层、夹杂等缺陷,且各项力学性能均符合ASTM B898—2005标准,能够满足装备的使用要求。     

感应加热温度对冷?热轧制成形钛/钢复合板界面的影响

对钛/钢组坯进行冷轧预复合成形,将钛/钢预复合板感应加热至热轧温度后单道次热轧成形制备了钛/钢复合板,研究了感应加热温度对钛/钢复合板的界面组织和界面结合性能的影响。结果表明,冷?热轧制复合法制备的钛/钢复合板的界面结合紧密,没有孔洞和间隙。钛/钢复合板由于感应加热和热轧的时间较短（<5 s）,钛/钢界面仅有少量硬化层碎块,没有金属间化合物析出。钛/钢复合板的界面Ti和Fe元素扩散层宽度随感应加热温度增大而增大,950 ℃时界面扩散层宽度达到8 μm。在感应加热温度为750 ~ 950 ℃的条件下,钛/钢复合板的界面结合良好。      

轧制钛／钢复合板过渡层的研究

为了确定轧制法生产钛／钢复合板时比较适合的过渡层材料,分别以紫铜他、镍N6、纯铁DT4做过渡层,对轧制钛／钢复合板进行了试制研究。以紫铜他、镍N6做过渡层时,选择了共晶温度以上和共晶温度以下两类加工温度;以工业纯铁DT4做过渡层时,在其共晶温度以下选定钛的相变点以上、钛的相变点以下两种加工温度。通过对这三种材料做过渡层时的轧制钛／钢复合板的实验结果进行综合对比分析,从而确定出纯铁DT4是轧制法生产钛／钢复合板时比较适合的过渡层材料。     

钛/钢复合板天然气炉退火处理的可行性研究

钛/钢复合板经爆炸复合后,存在较大的残余应力,因此,在生产过程中需进行消应力退火处理。天然气炉加热速度快,保温时间短,单炉承载吨位大,成本低,可用于热处理。但是由于钛/钢复合板中的钛易吸氢,易氧化,为此进行了钛/钢复合板在天然气炉中消应力退火的可行性研究。研究结果表明,在天然气炉中对钛/钢复合板进行消应力退火后,钛覆层表面无烧伤;氧含量无变化;氢含量增加0.001%～0.002%,满足氢含量<0.006%的要求;力学性能和耐蚀性均与箱式电阻炉退火的相当;钛/钢复合板整体的剪切性能也与箱式电阻炉退火的相当。西安天力金属复合材料有限公司两年来的生产实践也进一步证明,使用天然气炉对钛/钢复合板进行消应力退火,对其使用性能几乎没有影响,未出现不合格产品,而且缩短了生产工期,大幅度提高了生产效率,是完全可行的。     

钛—钢复合板钛复层的焊接技术

自从60年代中期钛-钢复合板出现以来,已大量应用于石化、冶金、医药、制盐等部门。由于钛、钢互熔问题尚未解决,故给钛-钢复合板的焊接带来了许多困难。目前钛-钢复合板的焊接工艺普遍采用钛复层和钢基层进行焊接,而复合层之间互不熔合。钢基层的焊     

钛/钢热轧复合新技术研究取得重大进展

钛/钢复合板由于其优异的耐蚀性和显著的经济性而被广泛地应用于各工业部门,尤其是石油和化工部门,但长期以来,钛/钢复合板只能用爆炸复合法或爆炸复合—轧制法生产,这些方法有许多不足之处,特别是钛/钢复合板面积只能达10～20m~(2)左右,远远不能满足大型石化设备的需求.近年来,日、法、美等国研究和开发了钛/钢热轧复合新技术,并取得了一定的进展.中国一些钢铁企业和有色企业也进行了这方面的跟踪研究.西北有色金属研究院进行了4年的研究工作,技术上已取得突破性进展,可望在近年内投入使用.     

高速铁路用钢轨生产技术

采用铌稀土(BNbRE)钢种,进行了钢的高纯净度、无缺陷连铸坯、高精度轧制、在线检验及相关技术研究,形成高级别钢轨生产工艺.结果表明:生产的钢轨能够满足<时速200公里客运专线60 kg/m钢轨暂行技术条件>的技术指标.     

关于高职教育终身化理念的思考

为了发挥高职院校在终身教育、终身学习、学习化社会的建设中的积极作用.对终身教育及高职教育终身化的理念进行了论述,提出了高职教育终身化的原则和构建终身教育及终身学习的体系.     

Guidelines for clinical use of drugs for involutional osteoporosis

Guidelines for clinical use of drugs for involutional osteoporosis will be released soon in Japan. Seven different types of drugs for osteoporosis are in market for clinical use in Japan. Those includes calcium, estrogens, anabolic steroids, calcitonins, active vitamin D3, ipriflavon, and etidronate. The guidelines recommend to clarify the risk factors in each patient before to start administration of drug. Patients with osteopenia are basically recommended to be followed without any drug treatment, but, patients with osteoporosis are generally recommended to be treated with drug after evaluation of risk factors. After menopause, inhibitors of bone resorption would be recommended as a first choice drug. For monitoring effects of treatment, bone mass measurement is so far the first choice, but bone metabolic markers would be used as well.     

Criteria for selection of patients for emergency portacaval shunt

A computer program analysis of the effect on survival of 74 preoperative factors was performed as part of a prosepctive study of the emergency portacaval shunt in 146 unselected patients with bleeding esophageal varices due to alcoholic cirrhosis. Only ascites, a serum glutamic oxalacetic transaminase level of 100 units or more, and a requirement for 5,000 ml or more of blood transfusion were associated with a statistically significant decrease in survival. However, none of these factors are contraindications to operation because their presence permits a survival rate of 37 to 40%. The only contraindication to emergency portacaval shunt is the combined presence of ascites, jaundice, encephalopathy, and severe muscle wasting, a constellation that was incompatible with survival beyond one year.     

The use of dimethylsulfoxide for fixation of yeasts for electron microscopy

Increasing numbers of young women with ovarian failure and women of advanced reproductive age (> 40 yrs) utilize oocyte donation to treat their infertility. In both groups, women who become pregnant frequently experience multiple gestation, occurring in up to 30% of pregnancies. Advanced maternal age and high-order multiple gestations are associated with an increased risk for obstetric complications. We reviewed the pregnancies of patients with high-order multiple gestations (> or = 3 gestational sacs) with respect to their antepartum course and neonatal outcomes. Mothers were divided into two groups according to age at conception; Group I (> or = 40 yr, n = 20) and Group II (< 40 yr, n = 10). These 30 high-order multiple gestations were found among 127 successful oocyte donation cycles (23.6% of all pregnant patients). Data regarding pregnancy outcomes were gained by chart review and telephone interview. Results demonstrated spontaneous reductions in the number of implantation sites were similar between groups (Group I: 21.4% vs. Group II: 17.6%). Multifetal pregnancy reduction (MFPR) was more often chosen by older women (Group I: 45% vs. Group II: 10%; P < 0.05). Antenatal complications were commonly experienced by both groups (> 80%) as were operative deliveries (> 85%). However, neonatal outcomes were generally good, with only one death occurring in the 79 delivered infants (1.3%). We conclude transferring supernumerary embryos to women undergoing ovum donation places patients at great risk for high-order multiple gestations. These pregnancies are associated with increased antenatal and neonatal complications. Although advanced maternal age is normally an added risk factor, well-screened older patients carrying high-order multiple gestations experienced similar outcomes as younger mothers.     

介绍一种生产冲挤用铝合金坯料的新工艺

哈兹列特铝板带连铸连轧工艺已被成功地用于铝和铝合金冲击挤压用坯料的生产。在对哈氏四个有关用户扫描的基础上，列举了其产品及其用途，并介绍了相关工艺及其优点。     

重轨孔型设计软件的编制

随着计算机在轧钢领域的广泛应用，重轨孔型设计利用计算机技术是今后发展的必然趋势，结合鞍钢大型厂的实际情况，编制了重轨孔型设计软件，应用该软件后，明显地提高了设计工作效率，加快了新产品的开发速度。介绍了该软件的编制方法、系统的功能及程序结构。