基于拉伸试验和冲击液压胀形技术,研究了不同退火工艺对H65黄铜管力学性能和成形性能的影响。首先,基于拉伸试验分析了不同退火工艺参数下管材的力学性能,结果表明,随着退火温度的升高,强度和硬度下降,塑性上升,保温时间对材料力学性能

Liquid impact forming (LIF) is a new composite forming technology based on tube hydroforming (THF) technology, which changes the volume of die cavity through impact load and rapidly generates internal pressure to realize tube forming. It does not need external pressure supply source, and it is low cost and high efficiency. In order to study the forming characteristics of the natural bulging area of thin-walled metal tube under different model side lengths and different closing velocities, the change of the cavity volume of thin-walled metal tube under impact hydraulic bulging was first analyzed theoretically, and a mathematical model of internal pressure was established. Then the effects of different loading parameters on the internal pressure, bulging height and wall thickness distribution in the natural bulging area of thin-walled metal tube were studied. Finally, through the comparison of finite element simulation analysis and experiment, it was found that the deviation between the experimental results and the numerical simulation was within 6%, which verified the accuracy and reliability of LIF. It also provides a certain theoretical research and application basis for the development of LIF of metal thin-walled tube. © 2023 This work is made available under the terms of the Creative Commons Attribution 4.0 International license,.

The contact state of a seamless internal threaded copper tube and an aluminium foil fin not only affects the heat transfer efficiency of a tube–fin heat exchanger but also seriously affects its service life. In this study, hydraulic expansion technology was used to connect the copper tube with an internal thread with a 7 mm diameter to the fin of the heat exchanger. The influence of the expansion pressure and pressure holding time on the contact state was analysed through experiments and finite element simulation, and the variation law of the two on the contact state was obtained. The contact state was characterised by the contact gap and contact area. In order to obtain the specific contact area value, a new method of measuring the contact area was developed to reveal the variation in contact area between the copper tube and the fin after expansion. The results show that the contact gap decreases with an increase in expansion pressure, while the pressure holding time remains the same. The contact area increases with an increase in expansion pressure, and the rate of increase slows. When the expansion pressure is 18 MPa, the average contact gap is approximately 0.018 mm. When the expansion pressure reaches 16 MPa, the contact area ratio is 91.0%. When the expansion pressure increases to 18 MPa, the contact area ratio only increases by approximately 0.6%. Compared with the influence of the expansion pressure on the increase in contact area, the influence of the pressure holding time on the contact area is lower. © 2023 by the authors.

为分析层压过程中不同槽型结构挠性基板对光纤应力应变的影响,采用COMSOL软件对光纤埋入不同槽型（U形、梯形、矩形）挠性基板的层压工艺进行仿真,分析槽型结构尺寸对光纤偏移量的影响,得到最优槽型结构。仿真结果表明,光纤埋入矩形槽挠性基板可降低光纤在层压过程产生的偏移量,且最优的矩形槽槽型结构的宽度与深度分别为125、145μm,此时光纤最大应力和最大偏移量分别为19.89 MPa、2.0403μm。

Rope saw technology played an important role in the field of high hardness material processing due to the high cutting efficiency, low equipment costs, energy saving and environmental protection. However, traditional wire saws can often become too slack for the beaded rope to cut due to reduced tension during the cutting process. A new diamond bead rope adaptive adjustment cutting method is proposed based on the conventional wire saw. Firstly, the three-dimensional structure of the beaded rope self-adjusting wire saw is modeled by SOLIDWORKS. Secondly, the modal analysis of the beaded rope adaptive adjustment wire saw is proposed based on the ANSYS. Thirdly, the kinematic model is established, and the dynamics of adaptive adjustment mechanism of diamond beaded rope wire saw is analyzed and verified by ADAMS. Finally, the mechanical property of the adaptive adjustment mechanism is analyzed by ADAMS and MATLAB co-simulation. The mechanical structure of the diamond wire saw is innovatively designed and its advantages are verified through dynamic analysis and co-simulation. This research IP:provides 203.8.109.10reference On:value Thu,for 09 the Mar optimization 2023 15:10:53 research of wire saw machine in the future.Copyright: American Scientific Publishers

为了更好地分析和研究电火花线切割技术,结合国内外学者的研究进展,全面分析与总结了线切割加工工艺参数对工艺指标的影响规律及工艺参数的优化方法。通过单因素实验法分析了电火花线切割中脉冲宽度、放电间隙、电流与电压等电参数对工

管材液压胀形是一种异型管坯塑性加工工艺,在轻量化和一体化中具有广阔的发展前景和应用价值,广泛应用于汽车制造、航空航天、医疗器械等领域。为了更加深入了解管材液压胀形技术的发展现状,结合国内外研究进展,对液压胀形环境下多通管

对绳锯机产品进行人机交互设计,改进其人机交互界面和产品交互功能,提高操作效率和用户满意度等。首先对绳锯机产品的国内外发展历程、研究内容和技术要点进行概述。其次归纳机械产品人机交互设计方法,并对绳锯机产品进行功能模块和设

针对当前办公椅形态设计与用户认知偏好之间缺乏客观实证研究的问题，提出一种利用眼动追踪数据分析获取用户对办公椅形态设计要素意向的方法。首先通过对办公椅形态设计要素进行分解，运用眼动实验提取并筛选视觉认知数据明确用户认知意向形态特征区域；其次基于专家对办公椅形态设计要素的评价，对各形态特征进行提取、分类和归纳，获取形态设计要素编码；最后将办公椅形态设计要素进行组合，采用李克特量表问卷和二次眼动实验进一步确定用户对办公椅整体形态设计特征的认知意向偏好。研究结果表明，不同形态设计要素对用户的办公椅选择偏好具有影响，办公椅产品整体形态意向偏好与靠背、扶手、坐垫3个重要特征形态要素的差异有着密切关联。研究准确把握用户的视觉认知特征，明确眼动指标与用户办公椅形态设计要素认知意向的关系，为后续办公椅形态设计提供科学有效的依据。

为提高绳锯机控制器界面交互的可用性水平,以可用性设计原则为基础,构建了基于眼动追踪技术和用户测试的操作界面可用性评价指标体系。根据用户行为特点,综合考虑产品界面的人机尺度和视觉感知需求,改进了控制器的人机界面交互设计方案,并将原界面和改进界面进行眼动试验评估,分析任务完成时长、正确率、至首次注视时间等眼动指标数据及热点图与轨迹图;结合用户测试和可用性量表法,从客观和主观两个角度对设计方案进行验证和评估。结果表明:改进界面的操作效率更高,有效提高了人机界面的可用性和用户满意度,该评估方法可为绳锯机控制器界面的人机交互可用性研究提供参考。