Regulating the surface microtopography of galvanized sheet for auto-body components

The use of new materials in the global auto industry is considered. The prospects for new production technologies based on IF steel with regulated surface microtopography are discussed.     

Formation of surface microtopography in the temper rolling of auto-industry steel sheet

A model is proposed for the formation of the surface microtopography in the temper rolling of cold-rolled steel sheet as function of the microtopography of the blank and the working rollers. In the model, temper rolling is treated as a linear system with several inputs and a single output. The results of simulation are compared with experimental data, and the model proves adequate.     

3D surface microtopography of cold-rolled and galvanized strip

The switch from 2D filtration to 3D filtration of surface microtopography is described. Important new surface parameters in the metallurgical industry are considered. The use of 3D parameters reveals new aspects of working-roller wear and the development of roughness at the surface of cold-rolled and galvanized auto-industry steel sheet and permits comparison of the surface roughness of coated and uncoated sheet. On that basis, the development of roughness on auto-industry steel sheet in temper rolling may be reassessed; the surface texturing of the rollers may be further improved; and the quantity of rolled metal obtained from a single pair of working rollers may be considerably increased.     

Production of thin sheet for shipbuilding

The production of thick NV D36 steel sheet according to DNV requirements has been introduced in sheet-rolling shop 9 at OAO Magnitogorskii Metallurgicheskii Kombinat.     

Production of cold-rolled sheet of increased strength

In sheet-rolling shop 5 at OAO Magnitogorskii Metallurgicheskii Kombinat (MMK), a production technology for 0.8–3.0 × 1180–1250 mm cold-rolled annealed strip made of 08γCЮT steel (strength class 275 according to Technical Specifications TU 14-1-3764-84) has been developed. Such sheet is used in stamping auto components. Technological parameters such that the product meets customer requirements on surface quality and mechanical properties are established.     

Production and properties of diamond-metal sheet materials

Conclusions The tensile strength of diamond-metal sheet materials bonded with a tin-nickel bronze can be increased by raising the nickel content of the binder, employing aging after quenching and cold working, and decreasing the grain size of the diamond powder. A study was made of the operating performance of diamond disks in the cutting of brittle nonmetallic materials. The size of cleavages on the work materials was found to be 11–21 m at diamond powder grain sizes of 3–20 m.Translated from Poroshkovaya Metallurgiya, No. 11(203), pp. 90–92, November, 1979.     

Monitoring the surface quality in sheet rolling

A system for monitoring the surface quality of hot-rolled strip produced on a 2000 continuous broad-strip mill is introduced on an experimental basis. Data on the surface defects permit improvement in sheet-production technology.     

高牌号无取向电工钢生产技术

介绍对大型水轮电机、汽轮发电机和节能高效电机用高牌号无取向电工钢所采取的诸如添加微量Sb、Sn、Se和Te合金元素等相应的措施，可以控制高牌号无取向电工钢中的CuS和MnS比例及形态分布，进而可以改善该钢的组织和织构，提高磁性。     

Production of high-strength hot-galvanized sheet from dual-phase steel

At OAO Novolipetskii Metallurgicheskii Kombinat, the first stages in introducing the production of high-strength hot-galvanized sheet (strength 450–600 N/mm²) from dual-phase steel have been completed. The manufacture of high-strength hot-galvanized sheet from dual-phase steel is possible on the existing (and aging) continuous hot-galvanization lines. The mechanical properties of the resulting hot-galvanized sheet correspond to the EN 10346 (EN 10336) standard.     

冷轧薄板表面缺陷研究

介绍了冷轧薄板表面主要缺陷的形貌、形成原因及预防措施。研究表明：冷轧薄板表面缺陷主要分为常规缺陷和非常规缺陷两大类。常规缺陷的产生与冷轧工艺质量密切相关,而非常规缺陷的形成机理则比较复杂,可能在炼钢工序也可能在轧钢工序形成,需具体情况具体分析。     

Production of high-strength steel sheet for the auto industry

The production of dual-phase ferritic-martensitic steel in the hot-rolled and hot-galvanized states is considered, as well as the production of cold-rolled steel microalloyed with phosphorus (≤0.12% P), which is characterized by increased resistance to residual denting. The mechanical properties of trial industrial batches for auto parts are outlined.     

镀锌板表面起皮缺陷原因分析与控制

利用扫描电镜和能谱仪,对超低碳镀锌板表面起皮缺陷进行检测分析,结果发现起皮缺陷与基体明显分层,且分层处嵌有大量的Al2O3夹杂,Al2O3夹杂尺寸5~100μm。查找该缺陷对应铸坯的浇铸过程发现,对应铸坯浇铸过程SEN水口堵塞、塞棒上涨。结合前期对SEN水口堵塞物的综合分析得知,SEN水口堵塞主要是由于脱氧产生的Al2O3夹杂引起。针对脱氧产生的Al2O3夹杂,通过工艺优化,改善钢包顶渣改质效果,提高渣中w(CaO)/w(Al2O3)至2.3,RH脱碳终点氧质量分数由367×10-6降低至315×10-6,实现超低碳镀锌板表面起皮缺陷的有效控制,缺陷发生率由0.10%降低至0.01%以下。     

IF钢合金化热镀锌钢带表面缺陷的研究

采用扫描电镜、能谱分析、X射线衍射和辉光放电光谱等技术对IF钢合金化热镀锌镀层表面缺陷形成的原因进行了分析.研究结果表明,黑斑缺陷是由悬浮渣和面渣与硅氧化物夹杂形成的;灰斑缺陷是由底渣形成的;深色波纹缺陷是由合金化工艺不当造成锌铁合金层局部生长到镀层表面形成的.     

粗糙度对热镀锌自润滑钢板表面摩擦特性的影响

在表面粗糙度分别0.82、1.23、1.68和2.07μm的四种热镀锌钢板上涂覆自润滑涂层制得热镀锌自润滑钢板,采用表面性能分析仪研究了热镀锌钢板表面粗糙度对热镀锌自润滑钢板表面摩擦特性的影响。结果显示,无涂层时钢板表面动摩擦因数较大,均在0.35以上,且随其表面粗糙度的增加迅速增加。当涂覆自润滑涂层后,自润滑钢板表面动摩擦因数均显著降低至0.15以下并在摩擦测试初期几乎保持不变,表明自润滑钢板表面粗糙度在摩擦测试初期对其表面动摩擦因数无影响。但在摩擦测试后期,自润滑钢板表面动摩擦因数逐渐增大,且增大幅度随着表面粗糙度的增加而增加。     

Production and application of Baosteel inorganic-lubricant-coated galvannealed automobile steel sheet

The inorganic-lubricant-coated galvannealed automobile steel sheet is a new product that improves the press formability of automobile body panels.In this paper,the production process,physical and chemical properties, press formability,and corrosion resistance of this new automobile steel sheet were discussed.Test results show that this inorganic solid-lubricant galvannealed automobile steel sheet has good surface friction characteristics and press formability.This product also meets the automobile industry's requirements for press formability,phosphate pro-perties,and corrosion resistance after coating.