An Advanced Oscillation Mixing Method for Improving the Cooling Uniformity in Quenching

In quenching, the cooling uniformity is most important to diminish distortion occurring on work pieces. As a trial to accomplish uniform cooling, therefore, there exist various mixing methods of a quenchant and the quenchant circulation with an external pump has so far been the well accepted mixing method. However, this study proposes an advanced oscillation mixing method that can improve more the cooling uniformity in quenching. The proposed method includes a stirrer in oscillating motion, so that the simultaneous oscillating and mixing movements of the stirrer are considered to provide efecfively the uniform cooling characteristics for the quenchant. In comparison with the case of the circulation pump mixing, the investigation using the oscillation mixing method has demonstrated the following two experimental facts:(1) the short vapor blanket stage caused by the quick breakage of the oil vapor blanket and (2) the reduced variation of the quenching distortion.     

Case Depth Measurement of Induction Hardening Using Image Processing

INDUCTION HARDENING of medium carbon steel iswidely used to produce automotive parts,agriculturalequipment and other machines.Inductor with highfrequency electric current was used as a heater totransform microstructure of steel surface into Austenite.Then water was sprayed on the heated steel.Austenitetransformed into Martensite.Area of microstructuralchange was considered to be case depth that was animportant parameter to be controlled in productionprocess.The standard procedure to de…     

The Integration of Vacuum Brazing into Heat Treatment - A Progressive Combined Process

The continuous constructive challenge to improve the functionality and efficiency of components always results in higher demands on production engineering, against the background of the generally increasing cost pressure. In many cases, you will just succeed in producing competitive and innovative products by combining and coupling of different procedures to an independent (hybrid) technology. The use of hybrid procedures for metal joining and heat treatment of metallic materials finds more and more industrial fields of application. Modern vacuum lines with integrated pressurized gas quenching are considered high-performance and flexible means of production for brazing and heat treatment tasks as well in the turbine industry as in the mould making and tool manufacturing industry. In doing so, the heat treatment is coupled with the brazing cycle in a combined process so that the brazing temperatures and soak times are adapted to the necessary temperatures and times for solution heat treatment and austeniting. This user-oriented article describes on the one hand examples of brazing of turbine components, but above all the practical experience from the plastics processing industry, where the requirement for a high-efficient cooling of injection moulding dies gains more and more importance.The combined procedure “Vacuum Brazing and Hardening” offers plenty of possibilities to produce mould inserts with an efficient tempering system in an economic way.     

Flexible Furnace Concepts for Vacuum Heat Treatment Combined with High-pressure Gas Quenching

IN the past five years the process combination of vacuum hardening, respectively vacuum carburizing with high-pressure gas quenching was successfully introduced to the market, especially in the manufacture of gears. In the meantime furnace concepts for various applications are available to the industry. In the following report three plant varieties are introduced, which differ in process flexibility and throughput. This report also explains criteria for the selection of a furnace in view of the existing application requirements. Besides this a short introduction is given into the vacuum carburizing process and the high-pressure gas quenching technology.     

Heat Treatment of Modified 6005A Alloy for Vehicles

HEAVY sectional aluminum with high strength is akey material to manufacture light-weigh,high-speedand modernized vehicles.Until now,most aluminumcarriage have been made of6X X X series alloys,among which6005A is an ideal one[1~5].However,it'sfound that6005A alloy is difficult to be quenched afterextruded on-line in industrial production,and thisgreatly influences its mechanical properties insubsequent aging'6"71.Considering that adjustment ofits composition may improve mechanical property …     

提高大型锻件冲击韧性的技巧

为提高大锻模件的冲击韧性，从不同的角度对其关键的影响因素进行了深入分析与探讨。同时，提出了改进措施。     

Intelligent temperature control system of quench furnace

1　INTRODUCTIONQuenchfurnaceisakindofkeyequipmentusedtoheattreatlargecomplexcomponentsofaircraftsorrockets ,withheightof 2 4m ,containingtwoheatingroomsandaworkroom ,withsteelboardssetbetweentherooms .Bothheatingroomsareseparatedintosixsections ,eachofwhichcontainsaheatingresistancecontrolledbyapoweradjuster .Workpiecesareputinworkroom .Acentrifugalelectromotorisusedtoblowhotairintoworkroomfromheatingroom .Thede mandofalloyintemperature risingrateandstableve racityatfixedtemperaturepointi…     

透明成核剂对聚丙烯的非等温结晶行为的影响

采用热分析方法研究了透明成核剂TM-3对聚丙烯(PP)非等温结晶行为的影响,并与纯PP样品作了比较.结果表明,TM-3能够提高聚丙烯的结晶温度12℃左右;分别采用了Avrami和莫志深方法对非等温结晶过程作了分析处理;对含有成核剂的PP样品的非等温结晶行为分析显示,成核剂的加入改变了聚丙烯的结晶行为,使其成核与结晶生长过程复杂化.     

渗碳淬火工艺因素对20CrNi2Mo钢热处理畸变影响的研究

采用正交试验方法,研究了淬火温度、渗碳温度、碳势、锻造比、预处理及预热等材料和热处理工艺因素对20CrNi2Mo钢热处理畸变的影响。针对20CrNi2Mo钢渗碳淬火的畸变特性,可通过优化的工艺参数较好地控制20CrNi2Mo钢的畸变。     

工件气体淬火过程数值模拟

用计算流体力学(CFD)的方法对工件气体淬火过程进行了数值模拟,在FLUENT平台上建立了真空高压气淬炉的三维非稳态模型,模拟了炉膛内流场和工件温度场的分布,模拟了圆柱形单工件淬火过程气体类型、气体压力和速度对冷却速度的影响,并模拟了多工件淬火冷却过程,预测了炉内不同位置处工件的冷却曲线。将模拟结果与实验结果相比较,两者基本吻合,为气体淬火工艺的优化提供了理论依据。