大型饼类锻件预镦粗工序的数值模拟研究

为了解决镦粗变形缺陷,将饼类锻件的预镦粗工序分为锥台砧镦粗和平砧端面整平两个阶段,利用DEFORM-3D计算平台建立锻造过程的有限元模型并进行仿真分析;分别从锻件内部的应力场和应变场等方面研究了锥台砧锥角和压下率对镦粗过程的影响,平砧旋转锻造方式和下砧砧形对端面整平过程的影响,以获得合理的预镦粗锻造工艺参数,指导实际生产过程。

预镦

A Study on Handover and Channel Allocation Scheme with Cost Function in Low Earth-Orbital Satellite Systems,A study on the short-circuit capability of field-stop IGBTs,A Tutorial on Optical Networks,A Two-Cell-Lookahead Call Admission and Handoff Management Scheme for Multimedia LEO Satellite Networks,Abstract Specification in Object-Z and CSP, ACCEPTANCE OF INTERNET CONTENT FILTERS: AN EMPIRICAL STUDY, Accurate and Efficient Prediction of Coverage Map in an Office Environment Using Frustum Ray Tracing and In-Situ Penetration Loss Measurement.

预镦

A Practical Nlulti-word Comparc-and-Swap Operation；A priority-bascd channel allocation scheme for cellular networks;A proposal of a method for limiting holding time to guard emergency communications from traffic congestion in cellular systems during major disasters; A QoS Providing Multimedia Ad Hoc Wireless LAN with Granular OFDM-CDMA Channel;A QoS Routing Mechanism for Reducing the Routing Inaccuracy Effects;A QoS-Aware Handoff using RSVP in Next Generation Wireless Networks;

预镦

A new method of blocking fault diagnosis on stator winding based on ANN; A new Si:C epitaxial channel nMOSFET architecture with improved drivability and short-channel characteristics;A new validated physically based IGCT model for circuit simulation of snubberless and series operation;A Novel 100 MHz-40 GHz RF Termination with Bias Network for Optical Systems;A novel channel allocation scheme in integrated wireless and mobile

热处理对AM50镁合金挤压管件力学性能的影响

着重研究了预镦粗、固溶和时效热处理对AM50镁合金挤压管材力学性能的影响,系统分析了在给定挤压比下几种处理对镁合金管材固态挤压力学性能的影响。结果表明:通过调整不同的处理方式,可大大改善管材的力学性能,对于挤压比λ=6的AM50镁合金挤压管材,经过热处理的性能Rm=273.6 N/mm2,Rp0.2=169.0 N/mm2,A=14.2%。

摆辗机用整体模具送料装置及汽车半轴坯件成形工艺

介绍一种摆辗机用整体模具送料装置及汽车半轴坯件的制作方法,采用整体模具摆辗成型生产汽车半轴坯件法兰盘,不产生分型面,法兰盘表面无毛刺,降低了后续加工难度,省时省力,提高加工效率和加工精度。

球头销钉球头成形仿真及优化

针对球头销钉球头成形困难的问题,提出一种预镦球头、终镦球头的2工位成形工艺方法,并应用有限元软件DEFORM-3D对球头成形过程进行数值仿真。分析预镦工位及终镦工位中各工艺参数对球头成形的影响,结合正交试验法,设计了以凹模圆角、锥角、摩擦系数、冲压速度、过渡圆角为试验参数的5因素4水平的正交试验,以成形过程中模具所受载荷最小为优化目标,通过极差及方差分析获得最优参数组合,即凹模圆角为0.2mm、锥角为20°、摩擦系数为0.05、冲压速度为10mm·s^-1、过渡圆角为3mm。最后,立足生产实际,验证仿真结果的可靠性,以在实际生产中能够有效地指导企业的生产。