2009年塑编产业概述与当前发展形势

本报告用数据论述了2009年塑编行业急剧增长的产业全貌,同时论述了产业十大热点:产业复苏急剧增长、新产业集群在形成、技术创新层出不穷、节能降耗如火如荼、食品认证进入尾声、原料改性提高品质、原料市场平稳升高、塑编标准修订启动、三届联谊会受赞誉、安全生产不容忽视。最后预测2010年发展形势。     

中国塑编产业回归理性发展2012年回顾及2013年展望

本年度报告在回顾塑编产业经过几年高速炽热发展后,到2012年已经下行回归理性发展。文中用数据论述了本年塑编行业平稳发展的产业全貌。同时论述了本年塑编产业的热点问题和面临的困境。最后预测了今年塑编产业发展趋势和热点问题。     

塑编产业“十一五”情况分析(一)

本文在回顾塑编产业十五发展状况后,详细地进行了十一五产量产品统计分析、十一五经济指标统计分析、十一五产业格局变迁分析。文中以大量珍贵难得的统计数据为基础,对塑编产业进行全面剖析。同时就十一五期间的塑编产业结构、技术创新、节能降耗等热点问题进行全面分析点评,最后指出十一五期间的塑编产业存在的问题。     

塑编行业发展的热点研究

塑编制品于上世纪五十年代末开始出现,于六十年代进入我国市场。塑编行业是一种介于塑料和纺织之间的以劳动密集型为主的边缘行业,于八、九十年代在我国经历一个飞速发展时期。当前,我国塑编行业仍然处于高速增长时期,发展态势良好。在深入分析当前我国塑编行业的发展现状的基础上,对当前的行业发展的热点进行深入探讨。     

浅谈技术进步对塑编生产企业的影响

随着塑料编织袋生产设备自动化水平的不断提高以及全自动制袋机、内粘膜机等新设备的成功应用,解决了塑编企业生产用人多、劳动强度大、生产效率低等困难,大幅提高了企业经济效益。内粘膜编织袋生产工艺必将取代传统的人工套膜、缝口工艺,成为生产具有防潮功能编织袋的新的工艺。     

浅谈塑编企业安全管理的重要性

本文论述了编织企业安全生产管理的重要性,针对塑编生产设备自动化程度的提高应当消除安全生产的各种误区。最后提出保障塑编企业安全生产的五项措施。     

对塑编挤出机性能参数的分析

本文主要介绍了塑编挤出机的主要组成,分析了螺杆挤出机主要工艺技术参数的确定,以及作为挤出机主要部分的螺杆的性能参数的分析。     

塑编产品生产中再生料的应用

目前，国内塑编产品竞争激烈，企业获利水平都较低。为了降低生产成本，各企业都在努力加强内部管理，深挖内潜，不断进行技术革新和技术改造，提高经济效益。在塑编产品生产中，如能有效地使用再生料，也可减小原料消耗费用，降低生产成本。特别是在塑编产     

质量检验工作是塑编企业技术创新的基本前提

创新是当前时代发展的主题和原动力。在创新思维的理念下,企业中的管理创新和技术创新是企业保持旺盛生命力的重要条件。在技术创新当中,质量检验工作又是技术工作的重要组成部分,也可以说是技术创新的基础和前提。     

编织袋新标准外观质量修订解读(上)

本文叙述了新标准GB/T 8946—2013《塑料编织袋通用技术要求》对袋的外观质量也进行了全面修订和增补主要原因和修改内容。并对袋的断丝、清洁、涂膜、粘合、褶皱、切断、缝合等外观要求修改内容作出了详细解读。     

The relationship of the volume fraction of martensite vs. plastic strain in an Fe–Mn–Si–Cr–N shape memory alloy

The volume fractions of stress-induced martensite formed by certain plastic strains were determined by X-ray diffraction and quantitative metallography in an Fe–Mn–Si–Cr–N alloy at room temperature. The results are fitted by least square method and are well consistent with an exponential function f_M=1−exp{−β[1−exp(−η)]ⁿ} deduced by Olson and Cohen, who used it to fit with experimental data for AISI304 stainless steel. The similarity of and β, as well as the difference in n for these two alloys are discussed in relation to their nucleation mechanisms.     

A method for the assessment of hyperstatic cracked structures in the elastic–plastic regime

This paper presents a methodology for the assessment of hyperstatic cracked structures constituted of high toughness materials which therefore break under Elastic–Plastic conditions. The method presented combines calculations based on Strength of Materials and Elastic–Plastic fracture mechanics to calculate the crack driving force applied to the cracked section by making its movements and those of the rest of the structure compatible. The application of the proposed assessment procedure is illustrated through the resolution of a practical example. The results of an experimental test, with the same geometrical configuration as the practical example, are also provided.     

电线护套中助剂成分的高效液相色谱分析

本文建立了电线塑料护套中助剂成分的高效液相色谱分析方法。实验中以甲醇为提取剂,对21个不同颜色的电线塑料护套样品中的助剂成分进行了提取和高效液相色谱分析。根据色谱图中特征峰峰数,保留时间,峰面积比的差异能够对其进行鉴别,为电线塑料护套检材与样品的比对检验提供了一种科学,有效的方法。     

Analysis of crack growth rate based on rotation at the crack tip plastic zone

The crack growth rate of a line crack is obtained from a linear elastic analysis of work required in the formation of a crack tip plastic zone. Equations of crack growth rate are derived from rigid body rotation at the root of Dugdale's plastic zone. The proposed relations are used to study the fracture behaviour of materials in tension tests and the three point bending tests. This revised version was published online in August 2006 with corrections to the Cover Date.     

2.5维机织复合材料经向拉伸弹性模量预测与试验验证

采用沿经向切片积分的方法计算2.5维机织复合材料的宏观经向拉伸弹性模量,与试验结果和传统的体积平均合成方法进行了对比,分析表明,本文中的方法能够有效提高传统体积平均法的预测精度.利用文中的方法分析了2.5维机织复合材料沿在机织循环过程中的经向拉伸弹性模量分布情况,并且对相关机织结构的2.5维机织复合材料进行了试验研究.研究发现,经纱弯曲程度较小的直联结构和添加平直经纱的衬经结构能够有效提高2.5维机织复合材料的经向拉伸弹性模量,并且能够改善经向拉伸应力-应变曲线的非线性.     

Inter-relation between true stress at the onset of necking and true uniform strain in steels – A manifestation of onset to plastic instability

A linear relation is observed between the true stress at the onset of necking and true uniform strain in type 316L(N) austenitic steel and P91 ferritic steel over wide range of test conditions. The observed linear relation between the true stress at the onset of necking and true uniform strain has been rationalised in terms of the onset to plastic instability. The strain regime, over which the alloy deforms by stable plastic flow, is directly proportional to the tensile strength.     

Closed-form solution for the size of plastic zone in an edge-cracked strip

This paper is concerned with the problem of plastic zone at the tip of an edge crack in an isotropic elastoplastic strip under anti-plane deformations. By means of complex potential and Dugdale model, the stress intensity factor and the size of plastic zone are obtained in closed-form. Furthermore, the analytic solutions for an edge crack at the free boundary of a half-space and a semi-infinite crack heading towards a free surface are determined as the limiting cases of the strip geometries.     

On the local elastic–plastic behaviour of the interface in titanium/silicon carbide composites

The purpose of this study is to conduct a high-resolution nonlinear finite element analysis of the elastic–plastic behaviour of titanium/silicon carbide composites subject to transverse loading. This class of metal matrix composites is designed for the next generation of supersonic jet engines and deserves careful assessment of its behaviour under thermo mechanical loads. Three aspects of the work are accordingly examined. The first is concerned with the development of a representative unit cell capable of accurately describing the local elastic–plastic behaviour of the interface in metal matrix composites under thermal and mechanical loads. The second is concerned with the determination of the influence of mismatch in the mechanical properties between the inhomogeneity and the matrix upon the induced stress fields and the plastic zone development and its growth. The third is concerned with unloading and the role played by the interface upon residual stresses. It is found that the maximum interfacial stress in the matrix appears in the case involving cooling from the relieving temperature with subsequent applied compressive loading. It is also found that the mismatch in mechanical properties between the matrix and the inhomogeneity introduces significant changes in the stress distribution in the matrix. Specifically, it is observed that the maximum radial and tangential stresses in the matrix take place at the interface. The plastic deformation of the matrix leads to a relaxation of these stresses and assists in developing a more uniform interfacial stress distribution. However, the matrix stresses and the resulting equivalent plastic strains still reach their maximum values at that interface. The results show similarities in the patterns of the interfacial stress distribution and plastic zone development for all ranges of fibre volume fractions and loading levels examined. However, they also show marked differences in both the magnitude and patterns of matrix stress distribution between the adjacent inhomogeneities as a result of interaction effects between the fibres.