焊接刀具PVD涂层值得关注的几个问题

PVD涂层在焊接刀具上的应用非常有限。利用多年涂层行业的工作经验,阐述了对焊接刀具进行PVD涂层时需要注意的问题,并针对这些问题提出了解决方案。根据这些方法,可以对焊接刀具进行正常PVD涂层,并能够大幅度提高焊接刀具的性能。     

深潜型海水液压动力系统的研究

以海水直接作为工作介质的海水液压传动在深海应用具有系统简单、维护方便等突出优势.研制一种深潜型海水液压动力系统,该系统由深潜电机驱动,压力10～14 MPa,输出流量30 L/min,设计工作深度4 000 m,该动力系统可用于驱动海水液压水下作业工具.介绍该系统的组成、工作原理、重要参数的选择和确定以及关键元器件的研制、水下漏电保护、污染控制等关键技术问题.目前,该系统已交付现场使用,试验表明,该系统很好地满足了海水液压水下作业工具的要求.     

金刚石车刀自动研磨装置图像处理系统的开发

本研究开发了能够应用于圆弧刃金刚石车刀自动研磨的图像处理系统,在使用基于形状的模板匹配的方法对车刀进行初始安装的基础上,进行了切削刃形状信息和位置信息的亚微米精度测量。测量结果表明:开发的图像处理系统实现了圆弧刃半径分别为1mm,0.5mm,0.2mm的金刚石车刀测量,能够在线获得自动研磨所需的形状信息和位置信息,在精度和效率上为自动研磨系统的开发提供了保证。     

数控机床刀具和刀具材料的发展动向

主要介绍数控机床刀具的简要分类、数控刀具材料的现状和发展趋势。     

基于三维CAD的智能化工装设计与管理系统研究

工装设计与管理是现代企业加工中的一个重要环节。这里分析了工装设计的特点;设计了基于三维CAD系统的智能化工装设计与管理系统,阐述了系统的结构、功能工作流程以及与其它系统的信息集成,并以UG的三维软件为基础实现了原型系统。     

大型装配工具制造工艺探讨

从企业制造加工的实际情况出发。通过对一个典型装配工具制造过程的详细分析，阐述了大型装配工具工艺制订的一般原则和基本方法，对企业工装制造技术的提高有一定的意义。     

Carbon doped α-Al2O3 coatings grown by chemical vapor deposition

Alumina (Al₂O₃) coatings deposited by chemical vapor deposition (CVD) with different modifications and dopants are widely applied as wear resistant coatings on cemented carbide cutting tools. The aim of this work was to investigate the influence of CH₄ addition on the deposition of α-Al₂O₃ by low-pressure chemical vapor deposition (LPCVD). The coatings were deposited at 1005 °C on a TiN–TiCN base layer using a precursor gas mixture of AlCl₃, CH₄, CO₂, HCl, H₂S, and H₂. Coating characterization was conducted by scanning electron microscopy (SEM), glow discharge optical emission spectroscopy (GDOES), X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectroscopy (ToF-SIMS), glancing angle X-ray diffraction (GAXRD), nanoindentation and tribological ball-on-disk tests against Al₂O₃ balls. Additionally, the ball-on-disk wear tracks were investigated by Raman spectroscopy.     

LF21铝合金双轴肩搅拌摩擦焊组织与性能

利用光学显微镜、扫面电子显微镜、显微硬度仪、拉伸试验机等方法,分析6 mm厚LF21铝合金单道对接双轴肩搅拌摩擦焊焊焊缝的微观组织、力学性能、缺陷成因。实验结果表明,转速1 200 r/min、焊接速度100 mm/min时可以获得较好的焊接性能;焊缝组织呈不完全对称的沙漏状;焊缝硬度在焊缝两侧的热影响区处发生不对称的软化,前进侧组织析出相发生了明显的长大现象;抗拉强度达到103.25 MPa,焊接强度系数为基材强度的70.4%,接头断口形貌呈典型的韧性断裂。     

内热式沸腾干燥器换热管组研制

内热式沸腾干燥器是聚氯乙烯生产中关键核心设备,换热管组是该设备上主要部件。本文介绍了换热管组的结构和制造难度。较详细地说明了为解决难点所用工装的结构和使用方法及采取的工艺措施。     

A systematic optimization approach for the calibration of parallel kinematics machine tools by a laser tracker

Parallel kinematics machine has attracted attention as machine tools because of the outstanding features of high dynamics and high stiffness. Although various calibration methods for parallel kinematics machine have been studied, the influence of inaccurate motion of joints is rarely considered in these studies. This paper presents a high-accuracy and high-effective approach for calibration of parallel kinematics machine. In the approach, a differential error model, an optimized model and a statistical method are combined, and the errors of parallel kinematics machine due to inaccurate motion of joints can be reduced by this approach. Specifically, the workspace is symmetrically divided into four subspaces, and a measurement method is suggested by a laser tracker to require the actual pose of the platform in these subspaces. An optimized model is proposed to solve the kinematic parameters in symmetrical subspaces, and then arithmetical mean method is proposed to calculate the final kinematic parameter. In order to achieve the global optimum quickly and precisely, the initial value of the optimal parameter is directly solved based on the differential error model. The proposed approach has been realized on the developed 5-DOF hexapod machine tool, and the experiment result proves that the presented method is very effective and accurate for the calibration of the hexapod machine tool.