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.     

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。     

水滴形歧管的结构分析

本文就衣架式模头水滴形歧管的结构设计，根据聚合物加工的流变理论，结合生产实际对水滴形截面的歧管流道分配系统进行分析，使得所设计的挤塑模在尽可能高的流速下，生产出符合尺寸及形状公差的均质片材。     

大口径内槽给排水管件模具

内环槽管性在给排水管网系统中具有施工方便、密封性高、伸缩区长、塑性较好的优点，但制件给模具带来了很多新的技术问题。介绍了模具环槽处内缩型芯的组合结构及抽芯运动原理，并总结了实际生产中，模具制造工艺及注射产品时应注意的问题。     

注射模装调实训室建设与运行机制的研究

从注射模装调一体化实训室的基础建设出发,延伸到实训室的内涵建设。为了实现注射模装调实训室的可持续发展,结合河南工业职业技术学院的实际情况,围绕实训室管理及制度建设、实训室教学工作的开展、实训项目的开发几个方面进行了运行机制的研究。     

铸造充型过程数值模拟的研究进展及应用

铸造过程的计算机数值模拟是当前公认的材料科学领域重要的研究课题,而充型过程的模拟是其中的难点之一.本文回顾了充型过程数值模拟技术的发展历程,综述了充型过程数值模拟技术的最新进展.简要介绍了目前国内外模拟软件的发展情况.针对"Z-CAST"系统阐述了数值模拟软件在铸造生产中的应用.     

移动硬盘盒精密热流道注塑模具设计

热流道注塑模具在模具行业中的应用越来越广泛,采用热流道系统不仅可以保证塑件质量、提高材料的利用率,还能显著提高塑件的生产效率。通过对移动硬盘塑料件的结构及成型工艺特点进行分析,设计了移动硬盘塑料件热流道注射模具,重点对热流道模具热平衡计算和热流道浇注系统进行了分析计算,模具采用单点热流道、一模两件潜伏式浇口、外滑块抽芯机构及斜推杆抽芯成型倒扣设计。实践证明,该移动硬盘塑料件模具设计结构合理,在提高塑料件成型质量的同时,提高了材料的利用率及生产效率,为同类结构特点的热流道注塑模设计提供了参考。