裂纹现象

According to quality problems of wall,it analyzes causes of cracks、scumming and abscission in mass cement sand pulp wall plastering ,and puts forward prevention measures to ensure beautiful view of wall.

针对工程墙面存在质量病害的现象，分析了大面积水泥砂浆墙面抹灰出现裂纹、泛霜、脱落的原因，介绍了其防治措施，以保证墙面的美观效果。

And some important phenomena which is very different from the stiff interface such as the interface debonding and sliding, crack defluxion, fiber bringing and pulling out have been successfully reproduced and revealed in the case of soft interface, accompanied result of acoustic emission is also presented.

可观察到考虑柔性界面时的界面脱粘、裂纹偏折、纤维桥联和拔出等现象，而刚性界面复合材料的破坏路径表现出完全不同的特性，同时得到相应的声发射模拟结果。

The results show that dynamical ductil-ity dominated final velocity of fragments. During tube expansion, the shear fracture appears preferentially a-long the adiabatic shear bands under positive stress, so the adiabatic shear band determines the size and shapeof fragments. Though the fragmentation behaviour of medium carbon Si - Mn bainific steel is close to that ofsteel 50SiMnVB, medium carbon Si - Mn bainitic steel is an ideal candidate material for the tubular bombs be-cause it is better in dynamical ductility, which can enable the tubes to gain high speeds before fragmentation.

结果表明：材料动态塑性是决定破片最终速度的主要因素；圆管膨胀时外表面形成以剪切为主的裂纹，并向内扩展，接近内表面的绝热剪切带伴随着圆管的膨胀而扩展，并未出现失稳现象，但在正应力的作用下成为优先的断裂通道、决定破片的尺寸和形态；中碳Si-Mn贝氏体钢与50SiMnVB钢的破碎性能相近，但贝氏体钢动态塑性很更好，破碎前的膨胀量较大、更有利于提高破片初速，是弹箭比较理想的候选材料。

The firebrick of secondary reformer dome has been turned up crack and breakage for many times maintenance,its service life is too short.

乌石化化肥厂第二套合成氨装置的二段转化炉拱顶自投运以来，拱顶砖经多次检修，仍出现裂纹和破碎现象，使用寿命过短。

Firstly, the basic character of the remote filed eddy current is simulated and analyzed in case of two-dimension axial symmetry which approves the existence of remote filed eddy current phenomenon; the full circumferential defect model is investigated to approve the feasibility of using the RFEC techniques to detect the position and depth of defect; the pit corrosion、circumferential and axial crack models are simulated, and the defect character based on voltage plane polar plot and the changes of phase and amplitude are analyzed to supply the standard for defect reconfiguration.

首先，在二维轴对称情况下仿真与分析了远场涡流的基本特性，证实了远场涡流现象的存在；对全周向缺陷的远场涡流检测进行了详细研究，证实了远场涡流检测缺陷位置和深度的可行性；对点状腐蚀、轴向与周向裂纹三种非轴对称缺陷进行三维有限元仿真，利用相位差和幅值变化曲线与电压平面极坐标图对缺陷特征进行分析，为缺陷形状重构提供了依据。

The color of the products is argent grey metallic shine, smooth, unknit.

产品表面呈银灰色金属光泽、光滑、平整、不得有严重氧化现象，不得有欠烧、过熔、鼓泡、分层、裂纹等缺陷。

Mm. 7.5.3 Requirements for quality of weld joint's surface: a No crack, not fusional, bubble, slag, splash; b Surface of seam of pipeline with design temperature lower than -29℃, stainless steel pipeline and alloy steel pipeline with trend of harden quenching shall be free from undercut.

The surface shall be smooth 7.5.3 焊接接头表面的质量应符合下列要求： 28 SH 3501-2002 a 不得有裂纹，未熔合，气孔，夹渣，飞溅存在； b设计温度低于-29℃的管道，不锈钢和淬硬倾向较大的合金钢管道焊缝表面，不得有咬边现象；其他材质管道焊缝咬边深度不应大于 0.5mm，连续咬边长度不应大于 100mm，且焊缝两侧咬边总长不大于该焊缝全长的 10%； c 焊缝表面不得低于管道表面，焊缝余高Δh 应符合下列要求： 1 100%射线检测焊接接头，其Δh≤1+0.2b1，且不大于 2mm； 2 其余的焊接接头，Δh≤1+0.2b1，且不大于 3mm。

Starting with the toughening of ceramics, the subcritical crack growth model on monotonical loads was set up for the first time, and the V—K curves in the subcritical crack growth process and the effects on them were obtained by use of computer simulation.

首次从材料增韧入手，建立了单向载荷形式下亚临界裂纹扩展模型，并利用计算机数值计算获得裂纹扩展过程中V—K曲线及其影响因素，由此对多晶陶瓷材料疲劳现象的本质进行了分析。

The metal melt around the oblique crack tip passivates the crack tip and inhibits the cracking trend of main crack source.

在瞬间超强脉冲电流作用下，裂尖前缘发生了强烈的绕流热集中现象，斜裂纹裂尖附近金属熔化，钝化了裂尖，阻止了干线裂纹源的开裂趋势。

In order to gain sample with smooth surface and uniform thickness, it was necessary to optimize molding and carbonization process.

过高的压力和过快的碳化速率易使制品出现裂纹、空洞现象。

It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.

从鲍尔点的形成原理出发，分析对称连杆曲线上鲍尔点的产生条件，提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。

The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.

集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品，年生产总值3000万美元，产品价廉物美、选料上乘、质量保证，深受国内外客户的青睐