共查询到20条相似文献,搜索用时 140 毫秒
1.
采用连铸工艺生产的TP347H钢坯存在Nb偏析现象,偏析严重时,经热连轧后的管坯在斜轧穿孔时易产生内壁开裂,导致钢管成材率和综合性能降低。针对偏析现象,通过热力学计算和试验相结合的方法研究含Nb析出相的析出行为,分析影响连铸钢坯Nb偏析的主要因素和一次MX相(碳氮化铌)析出物的特征。结果表明,采用连铸工艺生产的TP347H钢成分优化应以C、Nb元素含量为主;连铸TP347H钢坯Nb的偏析现象存在于钢坯中心区域,导致了钢坯边缘与中心区域的一次MX相析出物形貌、尺寸的差别。 相似文献
2.
3.
4.
法国一家研究机构研究了碳、硫、磷对连铸钢坯热裂的影响,共进行了三组碳锰钢的试验,每组试样的碳、硫、磷含量各不相同。试验时按拟定的工艺流程对试样进行冷却,以研究这三种元素对连铸钢坯内部热裂纹产生的影响。 相似文献
5.
6.
电磁搅拌在连铸钢中的应用据"Cmaπb"1995年No.8P31报道,在连铸过程中采用电磁搅拌的实践经验表明,钢坯质量很大程度上取决于结晶线内钢水流动速度和钢坯液芯内搅拌范围的大小。本文是对采用传导式电磁搅拌时连铸坯液芯内流体动力现象的数学分析结果进... 相似文献
7.
8.
介绍了连铸钢坯在步进式加热炉内加热时,测试钢坯实际加热温度的设备和方法。以在石钢中的应用为例,分析了目前步进式加热炉的加热效果,提出了相应的改进措施,并探讨了温度均匀性对弹簧钢脱碳层的影响。 相似文献
9.
10.
为了探究不同起爆位置下条形药包全场应变以及裂纹动态断裂特性,采用爆炸荷载动态焦散线实验系统和数字图像相关方法(DIC),开展了爆破模型实验研究。研究结果表明:条形药包一端起爆时,起爆点处翼裂纹扩展长度最小,随着炸药爆轰的传播,翼裂纹扩展长度增长;中心起爆时,中心位置翼裂纹扩展长度小于两端位置翼裂纹扩展长度,一端起爆时非起爆端翼裂纹扩展长度最长。无论中心起爆或一端起爆,条形药包中心区域翼裂纹扩展主要为Ⅰ型裂纹,并且中心翼裂纹起裂韧度最大,端部翼裂纹为以Ⅱ型为主的Ⅰ?Ⅱ型复合裂纹。一端起爆时,拉压应变作用范围沿炸药传爆方向传递,且非起爆端拉压应变作用区域大于起爆端,压应变最大值为距起爆点约0.67 ~ 0.83倍的装药长度。中心起爆时,拉压应变的作用过程沿起爆中心向两端呈对称形式传播,中心点位置应变最大。两种起爆方式下都出现端部压应力集中现象。 相似文献
11.
本文通过研究铁基熔覆层裂纹的开裂形貌、扩展方向、裂纹源、断口特征等开裂行为探讨了其开裂机理.结果表明:熔覆层表面裂纹起源于熔覆层和基体结合处,垂直于焊道向表面扩展,且贯穿整个熔覆层表面,呈沿晶开裂特征;熔覆层中存在的孪晶,可提高熔覆层的塑性和韧性,降低了熔覆层的开裂倾向;熔覆层中的δ铁素体,可以增强熔覆层的抗热裂纹能力;开裂的熔覆层δ铁素体中存在大量体心立方结构的含Si复杂固溶体(C-Fe-Mn-Mo-Si),且δ铁素体含量较少,是导致其韧性下降、裂纹出现的主要原因. 相似文献
12.
M. A. Anoshin L. Ya. Gabzetdinova E. A. Kozlov S. E. Kuratov O. V. Ol’khov S. S. Sokolov V. I. Tarzhanov E. V. Shuvalova 《Russian Metallurgy (Metally)》2012,2012(4):269-273
The acceleration dynamics and fracture of 12Kh18N10T steel shells loaded by the detonation of a spherical explosive layer are numerically simulated. NAG-type and some other fracture calculation techniques are shown to correctly describe the experimental results obtained in this work. 相似文献
13.
�����У����գ���������£�Ф�� 《钢铁研究学报》2013,25(11):42-48
The stainless steel/iron chips core cladding bar was hot-rolled by using recycling iron scrap. The interface of the metals and the influence of rolling pass, rolling temperature, graphite additive on properties of stainless steel/iron chips core cladding bar were analyzed by optical microscope, SEM, EDS and micro hardness tester. The experimental results show that element diffusion occurs at the interface after six passes rolling and the width of diffusion zone is about 70-80??m. The Fe of carbon steel diffuses into stainless steel and the Cr, Ni, Mn of stainless steel diffuse into carbon steel which makes micro hardness of carbon steel near the interface increase obviously. The bonding strength between stainless steel and iron chips core increases with increasing of rolling passes and it is 355MPa after six passes rolling. The tensile strength and elongation of the cladding bar increase with increasing of rolling temperature and they are 470MPa and 32% at 1150??, 500MPa and 35% at 1250??. The composition of iron chips core is improved by adding graphite powder. With the increasing of the graphite in iron chips, the tensile strength of cladding bar increase, but decrease for elongation. White reticular secondary cementite is appearing when the graphite is 1. 0% and the tensile strength is up to 736. 5MPa, the elongation decrease to 16%. The tensile fracture shows brittle fracture morphology. 相似文献
14.
15.
V. V. Satya Prasad G. Madhusudhan Reddy 《Transactions of the Indian Institute of Metals》2012,65(2):135-143
The surface properties such as wear, corrosion, oxidation resistance etc., can be improved by using suitable cladding technique. The most commonly used cladding material is stainless steel for cladding on carbon and low alloy steel base materials. Mechanical properties are considered important for satisfactory performance of clad joints used in several defence applications. In this work, cladding of a high strength low alloy steel with stainless steel was carried out using explosive cladding and electroslag strip cladding processes. The relationship between mechanical properties and microstructure of clad materials was evaluated. The bond interface in explosively clad material shows a wavy interface compared to strip clad interface. Electron probe microanalysis revealed that inter-diffusion of elements was significant in strip clad joints and insignificant in explosively clad joints. Shear strength, notch tensile strength and impact toughness of explosive clad joints are much superior compared to those in strip clad joints. 相似文献
16.
《钢铁研究学报(英文版)》2015,(10)
One-dimensional detonation model and two-dimensional P-M(Prandtl-Meyer) expanding model of double vertical explosive welding were established.A one-dimensional formula of flyer plate velocity was obtained and the bending angle curve representing flying attitude of flyer plate in double vertical was deduced as well.Compared with single parallel explosive welding,the double vertical explosive welding combines two cladding plates in one explosion.Due to closed charging structure,the influence of rarefaction wave on the plate's surface in double vertical explosive welding is eliminated and explosion loading time and displacement are increased,resulting in the increase of flyer velocity and energy utilization rate by 1.3 times to 1.6 times in different mass ratios.The analysis of microstructure in bonding zone of double vertical cladding plate under traditional charging shows that there is a clear over-melting near the interface,which is in line with the conclusion of detonation mechanism. 相似文献
17.
18.
为了确定在ZG06Cr13Ni4Mo不锈钢板上激光熔覆In625镍基合金粉末的最佳生产工艺参数,采用响应曲面分析法设计并开展一系列的激光熔覆参数实验,并利用Desigh-Expert软件中Response Surface模块对最终数据进行方差定量分析。通过金相显微镜对多道搭接熔覆试样的表面形态和横截面组织进行了观察和定性分析,从而确定熔覆工艺的最佳参数组合。结果表明,在维持送粉量不变的条件下,熔覆层高度对激光功率与扫描速度的响应都比较明显;熔覆工艺的最佳参数组合为激光功率2000 W,送粉量84 g·min?1,扫描速度5 mm·s?1,在此参数下获得的熔覆试样具有高质量的熔覆层,无气孔和裂纹,且表面光滑。 相似文献
19.
针对油气输送领域对耐H2S腐蚀油气复合管线的需求,采用真空轧制复合技术成功制备出825镍基合金/X65高强管线钢复合板。真空轧制复合技术是基于真空电子束焊接和热轧复合所开发出的一种新型复合技术,在高真空、高温和强塑性变形条件下,复合界面实现优异的冶金结合。采用X65/825合金/825合金/X65的4层对称复合轧制模式,并对复合界面的微观组织和力学性能特征进行分析。研究表明,复合界面连续平直,无孔洞和裂纹等缺陷,镍、铬和铁元素在界面两侧发生明显的扩散,另外复合界面生成一条连续的厚度约为1 μm的TiC薄带,在结合界面离散分布少量的颗粒状Al2O3化合物。界面平均剪切强度为404 MPa,拉剪断裂在复合界面处。 相似文献