电视机小后壳注射成型工艺的优化设计

以某品牌的电视机小后壳为研究对象,采用Taguchi方法进行注射成型模拟分析,研究了阀浇口开启时刻、熔体温度、模具温度、保压压力、保压时间等工艺参数对翘曲量和熔接线的影响。选取5个工艺参数为变量因素,利用Moldflow 2012软件按正交表进行模拟分析实验。通过综合分析,得到了以翘曲量和熔接线为优化目标的最优工艺参数组合,在实际生产时,为其成型工艺参数的选取提供一定的指导。     

基于Moldflow的电器联接件注塑分析与优化

为制定优化的某电器联接件的注塑工艺,利用Moldflow软件对初始方案进行了流动、冷却和翘曲等方面的模拟,预测了初始方案下可能产生的主要缺陷,探讨了熔接痕等缺陷产生的主要原因,提出了相应的解决办法。通过软件的浇口位置分析功能确定了最佳浇口位置,通过成型窗口的参数优化功能对成型工艺参数进行调整,工艺得以优化。同时,通过调整保压曲线,进一步减少了翘曲变形量,进一步优化了塑件的成型工艺。     

体操用S型弹簧踏板的力学性能优化

为实现对S型弹簧踏板的残余应力优化,利用Moldflow对注塑成型POE材料的弹簧踏板过程进行模拟分析,设计了两种浇口方案并进行对比分析优化。基于浇口优化方案结果,利用正交试验法得到最优成型参数组合。结果表明:对于两种浇口方案,采用单浇口的实验方案更加有利于减少成型周期,获得较好的流动前沿温度;正交试验结果表明,最终的优化参数组合:模具温度40℃,熔体温度185℃,注射时间20 s,保压时间25 s,保压压力12 MPa。通过优化的工艺参数组合可明显减少弹簧踏板的残余应力,获得较高质量的S型弹簧踏板。     

基于Moldflow的洗衣机平衡环叠层注塑模设计及工艺优化

针对洗衣机平衡环的产品特点进行了叠层注塑模设计,使用Moldflow软件对产品进行了充填及保压、翘曲模拟分析。通过模拟熔体充模过程,优化了浇口数量和流道尺寸,达到了流动平衡;通过对不同的保压方案进行保压和翘曲变形分析,确定了合理的保压控制方法和工艺参数。结果表明,该叠层模具能够很好地满足洗衣机平衡环的成型和装配要求。     

汽车CD面板成型工艺优化设计

应用UG10.0构建了某汽车音响塑件的三维数学模型,应用Moldflow Plastics Insight 2014对其浇口位置进行模拟分析, 确定了最佳浇口位置;为优化汽车音响塑件的注塑工艺,利用 Moldflow 软件进行了流动、冷却和翘曲等方面的模拟,探讨了收缩、翘曲变形等缺陷产生的主要原因。通过成型窗口的参数优化功能进行成型工艺模拟,在熔体流动速率、模具温度、保压压力、保压时间4个工艺参数的可行区间内,分别确定3个值,构建正交化模拟试验,利用极差法确定最优加工参数组合,提高了制品质量,缩短了汽车音响面板模具设计、制造周期。     

基于计算机仿真的注塑成型工艺优化研究

为了优化注塑成型工艺,研究了注塑成型的数学模型,以及产生翘曲形变的原因,在此基础上利用Moldflow软件对薄壁件塑料注塑成型过程中的宽浇口平板进行了仿真实验,并采用了无定型塑料丙烯腈-丁二烯-苯乙烯共聚物+聚碳酸酯(ABS+PC)对其进行注射、保压、冷却等流程模拟,选定了保压压力、熔体温度、冷却时间、模具温度、注射时间、保压时间等主要工艺参数,并通过方差比较的方法对这些工艺参数进行了评价,最终确定了注塑成型的优化方案。通过实验得出了ABS+PC的最优工艺参数组合,有效降低薄壳制件的翘曲量并优化了其制品性能。     

扫描仪面框注塑件翘曲变形的模拟分析

以扫描仪面框薄壁件注塑成型为例，应用Moldflow软件分析了模具温度、熔体温度、浇口位置和保压参数对翘曲变形的影响规律，提出了减小翘曲变形的工艺措施，分析结果与生产实际吻合。     

玻纤增强PPA节温器插头注塑成型多目标优化分析

基于Moldflow软件对玻纤增强PPA材料的节温器插头的注塑成型过程进行仿真模拟,考虑产品质量和圆柱孔区域的轴偏移量,利用L_9(3~4)正交试验进行工艺参数优化分析。基于Moldflow浇口定位器求解器,确定最佳的浇口位置。默认工艺参数分析表明:圆柱孔区域产生较大的翘曲变形和轴偏移量主要源于收缩不均效应。正交试验极差分析结果表明:各工艺参数对质量的影响程度排序为保压时间保压压力熔体温度模具温度;各工艺参数对轴偏移量的影响程度排序为熔体温度模具温度保压时间保压压力。综合考虑质量及轴偏移量得到最优工艺参数组合为A_1B_3C_3D_3,即熔体温度为280℃、模具温度为105℃、保压压力为90%及保压时间为12 s。优化工艺的模流分析表明:轴偏移量相比初始工艺降低8%,质量相比初始工艺降低9%。通过实际试模验证优化工艺参数在实际生产中具有可行性。     

响应面法在顺序注射成型工艺参数优化中的应用

以大尺度板条类塑料制品为例,集合CAE分析、试验设计和响应面代理模型技术,对3浇口方案下的顺序注射成型(SIM)工艺参数优化进行了研究。通过Taguchi方法,确定了对SIM制品综合成型质量指标影响显著的工艺因素,从大到小依次为中间阀浇口延迟关闭时间、熔体温度、注射速率、保压时间;基于响应面理论建立了可以适当描述SIM制品综合成型质量指标与主要工艺因素之间关系的评价模型;在确保模型高适配性的前提下,进而采用数据处理技术实现了对优化模型的求解,获得了最优工艺参数组合,即延迟关闭时间为0.4 s,熔体温度为210℃、注射速率为57.2 cm3/s、保压时间为10 s。经CAE验证最优工艺参数组合下的综合成型质量指标值的误差仅为5.2%,证明该方法合理有效。     

A 柱内饰件“一模两腔”注塑工艺参数优化

对 A 柱内饰件模型进行分析,得出浇口应选择潜伏式侧浇口,选择四点进料,模具设置成“一模两腔”结构。对熔体温度、保压压力、保压时间、冷却时间进行研究,得出在熔体温度232 ℃、保压压力 105 MPa、保压时间7 s、冷却时间29 s时,塑件平均体积收缩率为3.42 %。对该组工艺参数试验验证后,得出 A 柱内饰件音响口特征成型完全,没有因为内流道细长而产生缺陷,整体轮廓与检具间隙在允许范围内。     

注射成型工艺对PBT结晶和降解行为的影响

通过采用不同的注射条件,分别考察了熔体温度、模具温度、螺杆转速、注射速率、背压、保压压力、保压时间、滞留时间等多个重要的注射参数对聚对苯二甲酸丁二醇酯(PBT)小型制件降解程度、结晶形态和力学性能的影响。利用偏光显微镜、DSC、黏度计等,着重研究了各注射工艺参数对制件皮层厚度、结晶度、相对分子质量以及断裂伸长率的影响,从而为优化注射成型工艺过程提供依据。结果表明:熔体温度对制件各项性能的影响最为显著,而螺杆转速、背压、保压压力等的影响相对较小;随着熔体温度的提高和滞留时间的延长,PBT的降解程度迅速加剧,相对分子质量急剧下降,从而使制件断裂伸长率严重降低,力学性能变差。     

等静压成型 JB9014e 工艺研究

研究了比压、温度、压制次数、保压时间对ＪＢ９０１４ｅ炸药装药密度的影响。获得了优化工艺参数。     

A novel approach toward the effect of seal process parameters on final seal strength and microstructure of LLDPE

The optimization of heat-sealing process parameters, including time, temperature, and pressure, was performed on a monolayer linear low-density polyethylene (LLDPE) film. The seal properties examined for each process condition were: seal initiation temperature (T_si), plateau initiation temperature (T_pi), final plateau temperature (T_pf), plateau seal strength (SS_p), and failure mode. Increasing dwell time enhanced seal strength. However, it was found that the rate of this enhancement is different for each interval of dwell time. A narrow temperature plateau was observed for dwell times lower than 0.4?s and higher than 2?s, while in between a broad temperature window was observed. The pressure shows its influence up to the stage of wetting. And after providing the intimate contact between two film layers, additional increase in pressure does not enhance seal strength significantly. A 3D mapping of process safety zone was introduced for seal strength in the range of heat seal process variables for the very first time. The analysis of this 3D representation revealed that seal strength has a linear correlation with the square root of dwell time. In addition, the interfacial bond strength was shown to be proportional to the fraction of melted crystals. It was found that this fraction is determined by dwell time and temperature. Topography and morphology of surfaces after peeling revealed enlargement of fibrillar morphology to taller failure fracture complex shapes. Extensive roughness analysis on film surfaces after peeling found the much rougher surfaces after breakage of strong bonding.     

长玻纤增强聚甲醛注塑成型工艺的研究

制备了长玻璃纤维(LGF)增强聚甲醛(POM)复合材料。通过6因素2水平的正交试验,探讨了注射压力、注射速度、模具温度、保压压力、保压时间、冷却时间等工艺条件对LGF增强POM复合材料的制品表观和拉伸强度的影响。结果表明:注射压力、注射速度、保压时间和模具温度等4个工艺条件对LGF增强POM制品表观和拉伸强度的影响最大,当注塑成型条件分别为料筒温度180¹90℃、注射压力60 MPa、注射速度60 mm/s、模具温度80℃、保压时间15 s时,制品具有最佳的表观和力学性能。     

Influence of Process Parameters and Particle Size Distribution on Mechanical Properties of Tablets

The influence of the particle size distribution of maltodextrin powders with a dextrose equivalent level of 29 as well as two tableting process variables, namely the compression pressure and the dwell time, on the tensile strength, porosity, and pore size distribution of the final tablet was studied. The mechanical strength and porosity of the tablets are assessed in relation to the powder and process parameters. Regarding the process parameter, it was show that the compaction pressure clearly has a more pronounced influence on the tablet porosity and mechanical strength compared to the influence of the dwell time in the range of the study. As a result, the study offers a better understanding of how the properties of a tablet are influenced by the inter-correlation of powder characteristics and tableting parameters. Therefore, the shelf-life studies and tablet downstream processing as well as drug product development will benefit greatly from this work.     

Optimization of the spark plasma sintering processing parameters affecting the properties of polyimide

The present study deals with the optimization of polyimide (PI) mechanical properties, obtained by Spark Plasma Sintering (SPS), by using a method combining Design of Experiments (DOE) with physical, structural, and mechanical characterizations. The effects of SPS parameters such as temperature, pressure, dwell time, and cooling rate on the density, mechanical properties, and structure of PI were investigated. The experimental results revealed that the mechanical properties of the material were optimized by raising the sintering temperature up to 350°C. The optimized SPS processing parameters were a temperature of 350°C, a pressure of 40 MPa, and a dwell time of 5 min. Under these conditions, a relative density of 99.6% was reached within only a few minutes. The corresponding mechanical properties consisted of Young's modulus of 3.43 GPa, a Shore D hardness of 87.3, and a compressive strength of 738 MPa for a maximum compressive strain of 61.8%. Moreover, when working at 320°C and at 100 MPa, an increase in the dwell time was necessary to enhance the properties. Contrary to the other parameters, the cooling rate appeared to be a non‐significant parameter. Finally, correlations between the PI structure and the mechanical properties were made to demonstrate the densification mechanisms. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41542.     

木塑复合材料注塑工艺优化研究

采用正交分析法考察了机筒最高温度,注塑压力,保压时间,喷嘴温度对注塑木塑复合材料性能的影响,实验结果表明：在本试验中机筒最高温度对冲击强度和对拉伸强度有较大的影响,是影响冲击强度和对拉伸强度的主要因素,当最高机筒温度为185℃、注射压力为5.5-6.5 MPa、保压时间为10 s、喷嘴温度为200℃时为最优工艺。     

The Effect of Pressing Parameters on the Mechanical Properties of Plastic Bonded Explosives

Quasi‐static, uniaxial mechanical properties were measured for a series of PBX 9501 parts that were compacted using a permutation of various pressing parameters. Results were analyzed in terms of specimen density as well as pressing parameters. These data led to a second set of tests where PBX 9501 parts were compacted using various dwell times and temperatures, all other pressing parameters being held constant. Quasi‐static tensile data for these parts indicated that for the given range of parameters and specimen densities, the compaction temperature has a larger effect on the mechanical properties than does the dwell time. Moreover, for the range of parameters used, higher compaction temperatures and lower dwell times gave the compacted part more strength and toughness. Desired mechanical characteristics may be achieved by the appropriate selection of pressing conditions.     

Investigation on microstructure and properties of foamed (wood fiber)/(recycled polypropylene) composites

Microcellular foamed (wood fiber)‐reinforced recycled polypropylene composites (MFWPCs) were prepared by an injection molding process where azodicarbonamide was used as a chemical foaming agent. The influence of injection parameters (injection temperature, dwell pressure) on the microcellular structure (cell diameter and cell density) and the mechanical properties of the MFWPCs were investigated. The results indicated that when the melting temperature was 180°C and the dwell pressure was 12.5 MPa, a uniformly distributed microcellular structure of MFWPCs was obtained. Compared with solid wood plastic composites, the density of the MFWPCs decreased by 24.5%, and its impact strength of MFWPCs increased by 53%, because the propagation direction of the crack changed to the “skip” or “bifurcation” mechanism as a result of the microcellular structure, and the surrounding matrix of this structure made it easy to produce forced high‐elastic deformation. The toughening mechanism of the microcellular structure was analyzed. J. VINYL ADDIT. TECHNOL., 2012. © 2012 Society of Plastics Engineers