RTM工艺充填过程的动态仿真

建立了树脂传递模塑成型(RTM)工艺充模过程的数学模型,并采用有限元/控制体积法实现了对复杂薄壁构件的充填模式、压力场和速度场的动态仿真.算例表明,该法可以快速有效地描述RTM工艺的充填过程.     

主绝缘板树脂传递模塑技术研究

首先建立轻轨铁路绝缘器主绝缘板的树脂传递模塑充模过程的三维数学模型,然后对该模型进行了数值模拟分析,研究注射压力、树脂黏度等参数对成型过程的影响,最后提出了消除气泡缺陷的工艺条件.     

树脂传递模塑成型用高性能双马来酰亚胺改性树脂基体的研究

本文以烯丙基对甲酚醚（ＡＭＰＥ），作为双马来酰亚胺（ＢＭＩ）／二烯丙基双酚Ａ（ＤＡＢＰＡ）树脂体系的活性稀释剂，获得了适合树脂树脂传递成型（ＲＴＭ）工艺的三元共聚树脂体系。通过对该树脂体系及其固化物的粘度－温度－时间曲线，凝胶化特性、ＤＳＣ（微分扫描式量热）ＩＲ（红外光谱）、ＳＥＭ（电子显微镜扫描）和力学性能测试，表明该体系在ＲＴＭ成型 中，注射温度可取７０℃，该温度下，粘度仅０．３Ｐａ．ｓ，贮存     

一种适合于树脂传递模塑成型工艺的树脂基体及其碳纤维复合材料性能

选用一种液体改性芳香胺为环氧树脂的固化剂,得到了一种适合于树脂传递模塑(RTM)的高性能树脂体系。实验研究表明,该树脂体系在100℃时粘度仅为0.01Pa.s,在40℃时适用期在8h以上,Tg为107℃;其碳纤维复合材料抗剪切强度70MPa,抗拉强度1020MPa,抗张模量98GPa。说明该树脂体系粘度低,适用期长,玻璃化温度较高,与碳纤维的浸润粘接性好,可用作RTM成型工艺的高性能树脂基体。     

高性能复合材料树脂传递膜技术(RTM)研究

树脂传递模塑法（RTM）是一种低成本、效益好的复合材料成型工艺。研究了RTM用树脂体系、预成型技术、成型模具、成型工艺以及RTM在航空航天领域的应用。     

赛车车架树脂传递模塑工艺研究

本文着重叙述了仿生形态赛车车架选择的成型工艺及材料,同时对车架的树脂传递模塑（ＲＴＭ）工艺过程、工艺特点、基本原理及工艺质量控制作了简介。结果表明用ＲＴＭ成型的车架力学性能良好。     

高质量玻璃钢设备制作新工艺——RTM玻璃钢树脂传递模塑法

本文通过ＲＴＭ工艺与传统手糊玻璃钢工艺择比，说明ＲＴＭ工艺既能和糊工艺的模具成本低、开工费用小、设计灵活性大、操作方便的优点，又能制作出高质量、高水平玻璃钢产品。其发展前景十分广阔。     

树脂传递模塑工艺成型三维编织复合材料树脂体系研究

针对三维编织物的特点,研究出了适于三维编织复合材料树脂传递模塑(RTM)成型工艺的树脂体系。该体系具有黏度低、适用期长、力学性能及耐温性好的特点,能够满足RTM工艺成型高纤维体积含量的三维编织复合材料要求。     

顺序共注射成型充填过程的数值模拟

基于Hele Shaw流动模型,推导出顺序共注射成型充填过程的数值模型;并引入厚度分数,采用控制体积法来实现运动界面的追踪。数值模拟结果与moldflow的模拟结果相吻合,并且能够正确反映芯皮层熔体黏度比对注射压力和界面形貌的影响。     

Nonisothermal simulation on pressure during resin transfer molding

High speed injection has been widely used in resin transfer molding (RTM), which improves manufacturing efficiency. This sometimes leads to excessive pressure within the mold, resulting in fiber destruction and mold deformation. Heating the mold and injection resin reduces the viscosity of resin, leading to influence on mold internal pressure. Selection of optimal mold and injection temperature for effective reduction of mold internal pressure has become a source of concern in the polymer industry. This article presents an outlook relationship between mold temperature, injection temperature, and mold internal pressure. It also showcases a temperature selection method angle to addressing this issue. The “FLUENT” software has been secondarily developed that gives an insight in using the three-dimensional nonisothermal RTM simulation. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47492.     

气辅成型过程中可压缩空气流动数值模拟

气辅成型技术能够有效地改善产品力学性能、提高产品的质量,因此在注射成型生产中应用广泛,与之相应的气辅成型CAE技术也得到了快速发展。当前的气辅成型CAE技术中假定空气为不可压缩流体,忽略了空气的可压缩性,因此研究气辅成型过程中可压缩空气的流动行为具有一定的实际意义。针对气辅成型过程中可压缩空气流动的复杂行为,基于假设将复杂的三维(3D)流动问题转化为二维(2D)。采用 CBS方法建立2D瞬态可压缩空气流动的有限元分析模型,求解算法采用预共轭梯度法,并用VC++完成了算法编制,实现了可压缩空气流动过程的数值模拟,其压力结果可作为充填流动分析的基础数据。     

真空辅助成型技术及其配套基体树脂研究进展

综述了国内外关于真空辅助成型技术(VARI)及其配套基体树脂的研究和应用状况,介绍了VARI成型技术的主要原理、工艺流程及其对基体树脂的基本要求,并对国内外在VARI成型技术和配套基体树脂领域中的进展进行了适当的比较和分析。     

注射成型中聚合物剪切诱导结晶行为的三维模拟

在考虑剪切导致分子链取向并升高其平衡熔点的基础上,建立了基于Nakamura方程的剪切诱导结晶动力学模型。在WLF-Cross黏度模型中引入结晶对黏度系数的影响,构建了考虑结晶的注射成型过程模型。采用改进的有限体积法对聚合物剪切诱导结晶行为进行了三维数值模拟,模拟中耦合了流动场、熔体压力、温度、诱导时间与结晶度。结果表明,本方法可清晰模拟出注射成型过程中聚合物的三维“喷泉”流动行为以及3层“皮-芯”结晶结构,同时,诱导结晶时间指数与相对结晶度的模拟结果与理论及实验结果吻合。     

热塑性树脂基复合材料拉挤成型研究及应用进展

拉挤工艺是一种能够经济的连续生产复合材料的典型制造工艺,它不但具有其他成型方法的优点,且还具有其他工艺所不具备的优点,如生产效率高,重复性好,长度可任意切断,省原料、省能耗等.本文简要介绍了热塑性树脂基复合材料拉挤成型工艺的研究,以及国内外拉挤成型设备的发展概况.     

Curing kinetics and viscosity change of a two‐part epoxy resin during mold filling in resin‐transfer molding process

The curing kinetics and the resulting viscosity change of a two‐part epoxy/amine resin during the mold‐filling process of resin‐transfer molding (RTM) of composites was investigated. The curing kinetics of the epoxy/amine resin was analyzed in both the dynamic and the isothermal modes with differential scanning calorimetry (DSC). The dynamic viscosity of the resin at the same temperature as in the mold‐filling process was measured. The curing kinetics of the resin was described by a modified Kamal kinetic model, accounting for the autocatalytic and the diffusion‐control effect. An empirical model correlated the resin viscosity with temperature and the degree of cure was obtained. Predictions of the rate of reaction and the resulting viscosity change by the modified Kamal model and by the empirical model agreed well with the experimental data, respectively, over the temperature range 50–80°C and up to the degree of cure α = 0.4, which are suitable for the mold‐filling stage in the RTM process. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 2139–2148, 2000     

Elevated‐temperature vacuum‐assisted resin transfer molding process for high performance aerospace composites

Vacuum‐assisted resin transfer molding (VARTM) is commonly used for general temperature applications (<150 °C) such as boat hulls and secondary aircraft structures. With growing demands for applications of composites in elevated temperature environments, significant cost savings can be achieved by employing the VARTM process. However, implementation of the VARTM process for fabricating elevated temperature composites presents unique challenges such as high porosity and low fiber volume contents. In the present work, a low cost and reliable VARTM process is developed to manufacture elevated temperature composites for aerospace applications. Modified single vacuum bagging infusion and double vacuum bagging infusion processes were evaluated. Details of the method to obtain high quality composite parts and the challenging issues related to the manufacturing process are presented. Density and fiber volume fraction testing of manufactured panels showed that high quality composite parts with void content less than 1% have been consistently manufactured. A property database of the resin system and the composites was developed. A three‐dimensional mathematical model has also been developed for flow simulation and implemented in the ABAQUS finite element package code to predict the resin flow front during the infusion process and to optimize the flow parameters. The results of the present study indicate that aircraft grade composite parts with high fiber volume fractions can be manufactured using the developed elevated temperature VARTM process. © 2013 Society of Chemical Industry     

顺序共注塑产品质量控制及其数值模拟研究进展

顺序共注塑的影响机理很复杂，选择合适的材料和调整过程参数是常用的控制产品质量的方法。综述了材料性能和过程参数对产品质量（冲破趋势、界面形状、力学性能）的影响，并概述了数值模拟技术在该领域的研究现状及其发展趋势。     

过程参数对气辅成型的影响

本文基于Hele-Shaw模型，采用CAE技术，模拟了气辅注射成型中几个重要工艺参数：熔体温度、气体压力、延迟时间、熔体预注射量等对其成型的影响。并用流变学理论进行分析，揭示了各工艺参数对气辅注射成型的影响机理。     

PVC木塑复合材料生产中成型机的工艺控制

讨论了挤出机的机筒与螺杆装配精度、挤出工艺与PVC木塑复合材料塑化质量的关系,提出了调整、改善塑化质量的方法。