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Temperature change and stress distribution analysis of die surface in Al-alloy die casting process and experimental study on die heat check

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China Foundry 2008年第1期5卷 47-53页

作者： hu xinping Zhao Guoqun Wu Bingyao School of Material Science and Engineering Shandong University Jinan 250061 China School of Mechanical Engineering Shandong Institute of Light Industry Jinan 250353 China School of Material Science and Engineering Southeast University Nanjing 210096 China

The temperature change of the die surface in practical aluminum alloy die casting process was analyzed,and a 2D model was formulated on the basis of a deep concave round cavity without sliding core to analyze thestress distributions along the die surface in detail. Equipment was designed to test the thermal state of the die steelin different thermal loading conditions. The results of stress analysis showed that, the value of thermal stress (maximum1.5 GPa) caused in the die filling and die spraying stages was larger than the mechanical stress (maximum 85 MPa)caused in the die locking stage. The results of the thermal check experiment showed that there were three stages ofdie dissolving, and that the stress distribution shown by the samples' cracking routine was close to the die surfacestress analysis.

关键词： die temperature die stress die filling die locking die spraying die casting

Relaxor-like dielectric behavior and its effect on energy storage performance in P(TFE-HFP-VDF) terpolymers

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Science China(Physics,Mechanics & Astronomy) 2020年第2期63卷 150-153页

作者： KeWang Yi Jie Liu Yang Zhou xinping hu ShiHai Zhang BaoJin Chu CAS Key Laboratory of Materials for Energy Conversion Department of Materials Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China PolyK Technologies LLCState CollegePennsylvania 16801USA

Capacitors are critical components in many advanced electronic and electrical systems,such as pulse power systems,due to their fast charging-discharging speed and high power density[1-4].The ever-increasing demand for compact energy storage devices requires the dielectrics,which are the energy storage materials in capacitors,to have a higher energy density and low dielectric loss[2,3].Furthermore,a stable high-temperature performance is another important parameter to be considered for some applications in which high-temperature conditions are present,such as hybrid vehicles[4-7].

关键词： dielectric energy performance

Large effective piezoelectric response from the spontaneously polarized surface layer in P(VDF-TrFE)arch films

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Journal of Advanced Dielectrics 2022年第6期12卷 40-47页

作者： xinping hu Yuhong Zhu Baojin Chu CAS Key Laboratory of Materials for Energy Conversion and Department of Materials Science and Engineering University of Science and Technology of China No.96 Jinzhai Rd.HefeiAnhui 230026P.R.China

In this work,we show that a d_(33)~150 pC/N can be obtained in nonpoled poly(vinylidene fluoride trifluoroethylene)(P(VDF-TrFE))copolymer films with an arch *** copolymer films,which are often thought to be homogeneous,are in fact inhomogeneous in microstructure and physical properties after film *** a large proportion of the copolymer film is nonpolar,as expected in a nonpoled ferroelectric film,the surface regions of the film are spontaneously *** propose that inhomogeneous stress in the surface regions,which is either from the constraint of the substrate or skin layer effect formed during the film fabrication,generates a flexoelectric response and orients the spontaneous polarization of the ferroelectric *** a result of the polar surface regions,the nonpoled films exhibit a piezoelectric *** piezoelectric response is further amplified by the special arch structure of the films,leading to the observed large effective piezoelectric *** study not only discovers the polar surface effect in ferroelectric polymer films,but also proposes an approach to design polymer materials with a strong piezoelectric response.

关键词： Ferroelectric films dielectric polarization piezoelectricity surfaces

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压铸机连杆型喷涂机械手结构设计及其优化

特种铸造及有色合金 2007年第2期27卷 120-122页

作者：胡心平赵国群山东大学材料科学与工程学院

设计了与压铸自动化生产相适应的连杆型脱模剂喷涂机械手,并对该机械手的相关结构参数进行了优化处理和选择。所设计的连杆型喷涂机械手可以实现对不同模具型面形状和模具厚度、不同铸件大小和厚度的模具进行脱模剂喷涂。应用线性加权法... 详细信息

设计了与压铸自动化生产相适应的连杆型脱模剂喷涂机械手,并对该机械手的相关结构参数进行了优化处理和选择。所设计的连杆型喷涂机械手可以实现对不同模具型面形状和模具厚度、不同铸件大小和厚度的模具进行脱模剂喷涂。应用线性加权法,采用Mathematic软件,通过调整取得了喷涂机构的结构优化参数,并利用自身编制的软件进行了验证。该机械手可以广泛地应用于自动压铸喷涂,稳定和提高喷涂质量。

关键词：结构设计机械手参数优化压铸

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压铸脱模剂喷涂新工艺——脉冲喷涂

特种铸造及有色合金 2005年第3期25卷 158-159页

作者：戴挺胡心平吴炳尧东南大学山东轻工业学院

提出了一种新型的脱模剂喷涂工艺———脉冲喷涂。利用有限元方法对脉冲喷涂和传统的连续喷涂进行了初步对比分析 ,并在压铸厂进行了一定模次的实效验证 ,结果表明脉冲喷涂使得模具内的温度梯度比传统连续喷涂时的温度梯度大幅降低 ,有... 详细信息

提出了一种新型的脱模剂喷涂工艺———脉冲喷涂。利用有限元方法对脉冲喷涂和传统的连续喷涂进行了初步对比分析 ,并在压铸厂进行了一定模次的实效验证 ,结果表明脉冲喷涂使得模具内的温度梯度比传统连续喷涂时的温度梯度大幅降低 ,有利于减小热应力的产生 ,从而提高模具寿命 ,同时可减少脱模剂的使用量 ,改善铸件表面品质。

关键词：压铸脱模剂脉冲喷涂

微量稀土钇对Al-7Si-0.3Mg铸造合金的强化及共晶转变温度的影响

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稀有金属材料与工程 2022年第8期51卷 2947-2954页

作者：胡心平李瑞鑫王青齐鲁工业大学机械与汽车工程学院山东济南250353 齐鲁工业大学山东省机械设计研究院山东济南250353

采用拉伸实验,硬度测试,微观组织OM及SEM(+EDS)分析,XRD,DSC等方法,研究了微量钇(质量分数分别为0.025%、0.05%、0.075%、0.1%)以及T6处理对铸造Al-7Si-0.3Mg合金的组织性能及其共晶转变温度的影响。结果表明,钇微合金化后的Al-7Si-0.3M... 详细信息

采用拉伸实验,硬度测试,微观组织OM及SEM(+EDS)分析,XRD,DSC等方法,研究了微量钇(质量分数分别为0.025%、0.05%、0.075%、0.1%)以及T6处理对铸造Al-7Si-0.3Mg合金的组织性能及其共晶转变温度的影响。结果表明,钇微合金化后的Al-7Si-0.3Mg合金的屈服强度(YS)、抗拉强度(UTS)和延伸率(El)均有所提高,以0.05%Y含量的综合性能最佳。结合微观组织分析表明,强化相主要为Si相和Mg_(2)Si相,且Mg_(2)Si往往伴随着Si相存在。微含量的钇使α_(Al)+β_(Si)→Liquid反应温度下降(分别下降1.1、2.0、1.4、2.2℃),且使α_(Al)→Liquid反应温度有所提高;适量的钇促进α-Al异质形核基底的形成,且与β_(Si)和Mg_(2)Si等形成多元相,提高凝固时的过冷度。

关键词： Al-7Si-0.3Mg合金钇微合金化共晶转变温度断口分析 DSC分析