轧制过程轧辊磨损数学模型试验研究

利用自行开发研制的DTW-166热磨损试验机,研究了高铬铸铁、高速钢轧辊的磨损量与工艺参数的关系。分析了现场轧制过程中正在使用的轧辊磨损模型,对该数学模型在结构上进行了改进,利用各种条件下的大量试验数据,回归得到热轧带钢轧辊磨损的数学模型。该数学模型的建立为提高设定计算中的板形控制功能提供了理论基础。     

Influence of annealing treatment on microstructure and properties of cold sprayed stainless steel coatings

304 stainless steel coatings had been deposited on carbon-steel substrate by cold spray technique, vacuum annealing treatment was applied to the coatings with different temperatures, and the influence of annealing treatment on the microstructure and electrochemical behavior of the coatings in 3.5% NaCl were analyzed. The results indicated that, the cold sprayed coating was constituted by the flattened particles, and the interfaces were clearly observed between the deposited particles. It was also found that...     

Fracture behavior of 304 stainless steel coatings by cold gas dynamic spray

304 stainless steel coating was deposited on the Interstitial-Free steel substrate by cold gas dynamic spraying (CGDS).Three-point bending test of the cold sprayed 304 stainless steel coating was tested by SHIMADZU electro-hydraulic servo-controlled fatigue testing machine and the fracture morphology was examined by scanning electron microscopy.The results showed that the fracture behavior of the cold sprayed 304 stainless steel coating was brittleness fracture.The crack in the coating occurred in the interfaces between particles and the crack extended to the internal of the coating with the increase of the load.When the crack has extended to the combination interface between coating and substrate,the crack extended to the two sides.The microstructure and mechanical property of the cold sprayed 304 stainless steel coating have been optimized after heat treatment.     

模拟热轧工艺条件下304不锈钢的氧化行为

通过TGA(热重分析)测定了在模拟热轧过程的1000℃～1200℃空气中304奥氏体不锈钢短期氧化过程的质量变化,并采用SEM、EDS、GDE-OES,XPS和XRD等手段观察和分析了氧化膜的形貌、组成与结构.结果表明:在1000℃和1100℃氧化60 min的时间内,304不锈钢的氧化过程基本遵从抛物线规律;在120...     

大型锻钢支承辊生产状况及最终热处理工艺

概述了支承辊的工作条件及性能要求,国内大型锻钢支承辊的生产状况、工艺及设备;重点介绍了大型锻钢支承辊的最终热处理工艺,包括差温淬火、感应淬火。     

节约型双相不锈钢2101高温变形过程中微观组织演化

采用电子背散射衍射技术(EBSD)和TEM研究了节约型双相不锈钢2101在温度为1000℃和应变速率为5 s~(-1)的高温变形过程中的微观组织演化.结果表明,铁素体和奥氏体都发生以小角度晶界不断向大角度晶界转变为特征的连续动态再结晶(CDRX).固溶退火后双相不锈钢奥氏体内出现大量退火孪晶.随变形量增加,奥氏体中具有∑3位向关系的晶界逐渐消失.高温变形过程中双相微观组织演化机制的耦合作用共同决定了流变曲线特征.     

Characterization of Nanocrystallizatin Surface Layer of 0.4C-1Cr Low Alloy Steel Prepared by Ultrasonic Particulate Peening

NANOCRYSTALLINE MATERIALS,in recent years,have been attracting increasing interests,since the grainsize in the nanometer range leads to various unusualproperties[1].While it is known that most failures ofengineering materials occur on the surface.One kind ofsurface modification,the surface nanocrystallization(SNC),was introduced by Lu and Lu[2]in order toimprove the overall properties and behavior ofmaterials by inducing a SNC layer without changingthe chemical composition[3].Recen…     

Status and development of the comprehensive utilization of the steel slag at Baosteel

The steel slag at Baosteel mainly comes from basic oxygen furnaces(BOF),electric arc furnaces(EAF),continuous casting and hot metal pretreatment.The output of the steel slag at Baosteel was 4.43 Mt in 2010.The steel slag was utilized both within the company and across the society,and the utilization rate within the company achieved was 16%.This study describes the current status and existing problems in those technologies of treating and using steel slag,in the aspects of primary treatment,secondary treatment and advanced treatment,and it points out the development’s direction.     

利用共聚焦扫描激光显微镜观察一种常见高温合金的凝固过程

利用共聚焦扫描激光显微镜直接观察一种常见高温合金（IN718）的凝固过程。根据动态原位观察结果,凝固过程中的液相体积分数可以表示为时间或温度的函数,分析L→γ的凝固过程得到不同阶段的γ生长速率。利用Scheil方程对凝固过程中元素的偏析行为进行模拟,计算结果与原位观察结果相吻合。共聚焦扫描激光显微镜作为研究合金凝固行为的工具极具潜力。     

Influence of TiH2 addition on the solidification structure of Ti6A14V alloy during induction skull melting

Hydrogen,as a temporary element in titanium alloys,is very good in controlling microstructure.The microstructure and phase transformation of Ti6A14V alloy are affected by the amount of TiH,added into the melt of Ti6A14V alloy during the induction skull melting（ISM） process.This process,called melt hydrogenation,was studied in this paper through the use of optical microscopy,scanning electron microscopy（SEM） and transmission electron microscopy（TEM）.The results are as follows:after melt hydrogenation,both the solidification macrostructure and microstructure of Ti6A14Valloy are refined;theαphase precipitates in a lamellar form with the residualβphase from the grain boundaries;δ-hydrides precipitate during the solidification process as a result of the existence of hydrogen.The S phase with an F.C.C.structure can be observed by TEM in theαphase laminae of specimens with 1.25%TiH₂.In addition,the dependence of the microhardness of specimens on the weight percentage of TiH,added to the melt during the ISM process was also studied.