MgO的微波连接

用微波加热方法可以把两种氧化镁陶瓷连接起来。微波辐射时用莫来石隔热砖盖住连接部位,这就会很容易地在短时间内完成连接。随着连接温度的提高和压力的增大,接缝的抗弯强度会不断增强。接缝的强度要比基质的大。在2150K温度下用0.5MPa压力持续4分钟的连接试样,其最大抗弯强度为105MPa,大约是基质的70％。

PB(聚丁烯)管及其施工工艺

介绍了PB(聚丁烯)管的特点、应用场合和施工工艺、质量控制等,对塑料管热熔连接的质量缺陷控制提出了有效的对策。

聚丙烯(PP-R)供水管工程应用实例

聚丙烯(PP-R)管材是目前国际上广泛应用的先进供水管材之一。本文结合暨大新研究生楼供水系统的工程实例,试述了PP-R管的性能特点、材料的耐用度计算、管道的连接技术、热膨胀的补偿方法、施工中的存在问题及其处理方法等。

Investigation of Bed Joint Reinforcement Influence on Mechanical Properties of Masonry under Compression

The results of investigations of compressed reinforced masonry walls subjected to axial compression are presented. Tests were carried out using specimens made of clay bricks and cement-lime mortar. As reinforcement, smooth and spiral twisted longitudinal rods, two types of structural wire mesh and truss type reinforcement were used. Two percentages of bed joint reinforcement, about 0.1% and 0.05% were applied. For each type of reinforcement, three masonry walls were tested. Additionally, nine unreinforced models were also tested. The main aim of the investigations presented is to determine the effect of different types of reinforcement on the load capacity and failure. Measurement of the strains of reinforcing bars permitted the recording of the strain level at the moment of crack appearance and also at the moment of failure.

反应堆压力容器局部热处理残余应力模拟

以核反应堆压力容器为研究对象,运用ABAQUS软件,建立局部焊后热处理有限元模型,模拟了焊后热处理的加热、保温和冷却过程中的温度分布特性,及冷却过程中筒体内外表面的径向应力、环向应力和轴向应力的分布特性。结果表明,核反应堆终接环缝在焊后热处理过程中,由焊缝中心向两侧温度逐渐降低。加热区域温度随时间的变化与热处理过程基本一致,且温度场模拟效果与试验结果吻合较好。筒体冷却过程中的径向应力相对较小,随着距焊缝中心距离的增加,筒体内外表面的环向应力先减小后增大,最后趋近于零。冷却初始时刻焊缝中心筒体内外表面的轴向应力均达到最大值且内外表面应力近似呈对称分布。随着冷却过程的进行,筒体内外表面的环向应力、径向应力和轴向应力大小不断减小,筒体内表面的最大环向应力和轴向应力分别为-200 MPa和-240 MPa,外表面的最大环向应力和轴向应力分别为-98 MPa和230 MPa,最终空冷后的应力趋近于零。

PB（聚丁烯）管及其施工工艺

介绍了PB（聚丁烯）管的特点、应用场合和施工工艺、质量控制等，对塑料管热熔连接的质量缺陷控制提出了有效的对策。