轧制特殊钢高压除鳞分析和改进途径

特殊钢材料在轧制过程中一直存在除鳞效果不好的问题,本文分析了加热过程中氧化铁皮生成的机理,针对不同材料形成的不同氧化铁皮成分和致密程度,发现喷嘴的布置和选型对氧化铁皮的清除至关重要,通过理论分析对喷嘴布置和选型做了设计改进,并应用到生产实际中,取得了良好的效果,其结果喷嘴高压水冲击力比原来提高20%,满足特殊钢产品质量要求,同时比原设计节约水量约11%,确保了特殊钢热轧钢坯出炉表面氧化铁皮的清除。     

160 t钢包翻包机结构与功能

新型钢包翻包机是九十年代从国外引进的一种专用设备,其以高效、安全、便捷等特点越来越多的应用于大型钢铁厂.本文介绍了160 t翻包机结构与功能.     

Microstructure and Sliding Wear Behaviour of Ni(Cr)-TiB_2 Coatings Deposited by HVOF Spraying of SHS Powders

THERMAL SPRAYING provides a large range ofcoatings,which increase the wear resistance ofsubstrates[1].One of the major coating families is thecermet,composed of hard ceramic particles with ametallic binder.The most commonly used cermetcoatings in industrial applications are based on eitherthe WC-Co or the Cr3C2-Ni(Cr)systems with WC-17wt%Co and Cr3C2-25wt%Ni(Cr)being typicalcompositions[2,3].Although WC-Co deposits are hardand wear resistant at ambient temperatures their rangeof ap…     

Thixoforging of continuous fiber-reinforced AlSi/AlMg-alloys

High strength in combination with low density is the key features for lightweight constructions in automotive and aerospace applications. Tailor-made fiber reinforcements in light-metal matrices could help to achieve this goal. However, the integration of fibers with conventional casting-route manufacturing techniques like squeeze casting or diffusion bonding restricts the component geometry and results in elevated process cost due to long cycle times and the need of additional fiber coatings. In the center of competence for casting and thixoforging Stuttgart (CCT), new processes for manufacturing metal matrix composites are developed. Long-fiber reinforced Al–Si alloys and components are produced by thixoforging of laminates made of alternating metal matrix layers and carbon fiber fabrics. This paper illustrates the manufacturing technology and first experimental results with special focus on fiber penetration and infiltration behavior and also on the formation of fiber-matrix interface to analyze fiber damage by mechanical or chemical attack.     

Ni－Cr－B－Si合金粉末等离子喷涂层的高温性能及其在滚锻模上的应用

研究了Ｎｉ－Ｃｒ－Ｂ－Ｓｉ合金粉末等离子喷涂层的高温抗氧化性能、耐磨性、热稳定性，并介绍了其在连杆毛坯滚锻模上的应用．结果表明，这种涂层的某些高温性能大大优于５ＣｒＮｉＭｏ钢，在冲击载荷不大的场合，可以作为热锻模的强化方法．     

高温W/Re流口复合界面上的扩散层

W/Re流口在高温下使用时,复合界面处会发生反应扩散而形成一个由固溶体(W),双相σ,双相x,固溶体(Re)4个相组成的过渡层。并作出了不同反应扩散时间的浓度分布曲线,及浓度突变形成的双相区,从而确定了各相成份组成。对经反应扩散后的复合界面进行微观观察发现x相、σ相内有许多间隔式微裂纹,据此认为高温下W/Re流口失效原因是使用过程中上述两x,σ相内裂纹扩散,熔体渗入所致。     

Numerically optimal design for the system with coupled complex transport phenomena-application to the Submerged Entry<Emphasis Type="Italic">Nozzle</Emphasis> in continuous slab caster

This study presents a simple and robust algorithm for the optimal design of the system with coupled complex transport phenomena: the transport phenomena comprise fluid flow, heat and mass transfer. The (1+1)-Evolution Strategy method is adopted as the optimization method. In order to analyze the transport phenomena in the complex geometry generated during the optimization procedure, thefinite volume method with a boundary fitted curvilinear coordinate system is used. To confirm the validity of the present method, the optimal design for the inner shape of the simplified two-dimensionalSubmerged Entry Nozzle in the continuous slab caster is conducted. It is shown that the resulting design of the nozzle is consistent with the purpose and constraints of the design.     

薄板坯连铸浸入式水口结构数值模拟

使用有限元计算方法开展薄板坯连铸浸入式水口流场的研究 ,分别对水口不同浸入深度的流场分布、水口出口不同角度的流场分布进行计算。结果发现 :水口的浸入深度在 30 0mm时较为合理 ;水口的出口角度以R1 5、60°、45°为宜     

磷复肥喷浆造粒“三内”技术研究与开发(一)

介绍磷复肥喷浆造粒“三内”技术 ,该技术集喷浆造粒、分级、返料、破碎为一体在转筒内完成全过程 ,实现机头喷浆机尾出产品 ,粉体在筒内闭式循环造粒新技术     

裂解炉下集气锥形接管失效分析

通过化学成份分析、金相的宏微观考察、Manson-Haferd参数对锥形接管持久寿命的估算,以及热应力的计算,对锥形接管的失效原因进行了分析,认为是由温差应力导致失效。所以应该充分注意高温构件保温措施的有效性,避免非正常温差应力的产生。