聚合物流变性能对共注射成型的影响

在共注射成型多相分层流动充模成型机理的基础上，揭示了芯壳层熔体对共注射成型的分层界面形貌和芯层熔体前沿突破的影响，并模拟了芯壳层熔体粘度比对共注射成型的影响，建立了芯壳层熔体粘度与分层界面和前沿移动界面菜貌的关系。本文的模拟研究结果与一些文献的实验结果相吻合。     

拉深简形件水平浮动切边模设计

拉深无凸缘筒形件，由于拉深后筒口边部凸凹不平。采用移动式凸轮，在水平十字形四个方向使凹模浮动与固定的凸模形成相对的剪切刃口，将多余的不平整的边部切掉。每浮动一次切开圆周长的四分之一多一点，共浮动四次。     

模具沉积层应变的模拟

为分析沉积层应变的变化情况,并找出温度与形变的变化规律,采用有限元分析软件ANSYS计算并绘制不同时刻以及不同位置沉积层内的温度及应力应变曲线,在建立传热模型过程中考虑了金属液滴向沉积层的传热以及沉积层向系统外的热量散失等问题．采用在厚度方向以微小层逐层叠加来模拟涂层的增厚,并以此为基础构造沉积层有限元计算模型,应用单元生与死逐层激活层单元参与计算过程．实现移动边界以充分模拟真实的喷涂沉积过程．通过分析不同时刻以及不同位置沉积层内的应力应变曲线,获得了沉积层应力应变变化规律．结果表明,沉积层内存在残余塑性应变,且沉积层与母模接触部位等效应力最大,是最易翘曲的地方,验证了沉积层失稳的一般形式．     

食用色素对壳聚糖改性纤维染色性能的研究

为了研制符合食品包装要求的彩色防水纸浆模塑制品,选用食用色素对壳聚糖处理后的纸浆纤维进行染色,并在染色纸浆中加入防水剂H,讨论了防水剂质量分数对纸浆纤维防水效果和染色效果的影响。结果表明,染色温度为60℃,染料用量为0.6%(对绝干浆质量),染浴pH=3.5的条件下染色效果较好。结合生产实际,可进行常温染色,上染率达71.43%,褪色率为7.12%。防水剂的加入除能明显提高纸模制品的湿环压强度外还能改善其染色效果,添加量为5%(对绝干浆质量)时,纸模可达到较好的湿环压强度,上染率可提高到79.30%,褪色率降低为0.31%。     

Solidification and crystallization properties of CaO-SiO2-Na2O based mold fluxes

Crystallization properties play an important role in keeping a smooth running of continuous casting process and high sur-face quality of cast strands. To reduce fluorine pollution in slag, a new type of CaO-SiO2-Na2O (CSN) based mold flux was studied. The solidification and crystallization properties, including crystallization temperature, crystallization ratio and solidification minera-graphy, were measured, which were compared with the CaO-SiO2-CaF2 (GF) mold flux. The results show that the crystallization performance is equal to the high fluoride mold powder and CSN can be used for peritectic steel grades sensitive to longitudinal cracking in continuous casting.     

Characteristics of shell thickness in a slab continuous casting mold

The key to reduce shell breakout in the continuous casting process is to control shell thickness in the mold.A numerical simulation on the turbulent flow and heat transfer coupled with solidification in the slab mold using the volume of fluid (VOF) model and the enthalpy-porosity scheme was conducted and the emphasis was put upon the flow effect on the shell thickness profiles in longitudinal and transverse directions.The results show that the jet acts a stronger impingement on the shell of narrow face,which causes a zero-increase of shell thickness in a certain range near the impingement point.The thinnest shell on the slab cross-section locates primarily in the center of the narrow face,and secondly near the comer of the wide face.Nozzle optimization can obviously increase the shell thickness and make it more uniform.     

浅谈行动导向教学在高等职业教育中的应用

从教育的本质出发,针对高等职业教育的特点,讨论如何实施技能、知识、素质三位一体的高等职业教育。通过模具专业的实例阐述了行动导向教学理念,揭示了行动导向教学的本质"做中学"如何在模具专业中实施。总结了在模具专业中实施行动导向教学的得与失,并针对行动导向教学的各个环节的实施进行了有建设性的探讨。     

Mold deformation in soft UV-nanoimprint lithography

UV-nanoimprint lithography (UV-NIL) using a soft mold is a promising technique with low cost and high throughput for producing the submicron scale large-area patterns. However, the deformations of the soft mold during imprinting process which can cause serious consequences have to be understood for the practical application of the process. This paper investigated the deformation of the soft mold by theoretical analyses, numerical simulations, and experimental studies. We simulated the mold deformation using a simplified model and finite element method. The simulation and the related experimental results agree well with each other. Through the investigation, the mechanism and affected factors of the mold deformation are revealed, and some useful conclusions have been achieved. These results will be valuable in optimizing the imprinting process conditions and mold design for improving the quality of transferred patterns.     

潜伏浇口型腔板-推杆二级推件薄圆盘注塑模

设计了一种特殊的潜伏浇口型腔板-推杆二级推件薄圆盘注塑模，论述了模具结构特点和工作原理。该模具采用潜伏浇口型腔板-推杆二级脱模机构。推出塑件时，先依靠与塑件接触面积大的型腔板推动塑件，使塑件先与型芯分离，然后推杆将塑件推出型腔。模具结构简单紧凑，工作可靠，操作方便，成型塑件质量好。     

石蜡改性热熔胶的研究

本文介绍了一种石蜡改性热熔胶的配方和性能，实验结果表明：用于实型铸造的效果明显地优于现有的几种粘接剂。