基于磁致伸缩位移传感器的精密注射成型研究

以注塑机塑化部分位移传感器作为研究对象，分别采用传统电子尺和高精度磁尺作为注塑机的螺杆计量工具。在相同的工艺条件下，比较两种位移传感器的位移计量精度及由此得到的制品质量重复精度。考虑不同工艺条件对于位移传感器工作过程的影响，实验过程中采用了正交实验方法，针对螺杆预塑化量、螺杆转速、注塑速度和熔体背压4个相关工艺参数设定不同参数值进行实验方案的排列。实验结果比较了两种位移传感器的计量精度和工作稳定性，从螺杆位移高精度计量方面为提高精密注塑机制品重复精度探寻解决方案。     

棒料几何参数对其预制表面V型槽槽底应力集中系数的影响规律

针对研究新型低应力精密下料系统时,需要获得不同直径的带V型槽棒料几何参数对槽底应力集中水平的影响规律的问题,利用ANSYS软件,建立了系统棒料下料时的三维有限元模型。采用正交法设计了实验方案,通过有限元法的数值模拟实验,确定了使V型槽尖端应力集中系数最大的棒料几何参数的最佳取值条件,即槽外形夹角为90°,槽底圆角半径与棒料直径的比为0.005,槽深与棒料的直径比为0.15。实验研究表明,槽底圆角半径对应力集中系数的影响最大,棒料的直径与槽深对应力集中系数的影响较小,而槽外形夹角对槽底应力集中系数的影响程度最小。     

EPS模陶瓷型精密铸造失模工艺研究

针对EPS陶瓷壳型精铸失模时容易裂壳的现象,对EPS消失模精密铸造工艺进行了研究。利用自制的膨胀率检测设备对不同密度的EPS模试样在不同加热温度下的最大膨胀率进行了测试,研究了壳型膨胀与失模温度之间的关系;对陶瓷壳型中EPS模失模时的温度场分布进行测量,发现EPS模试样的密度大小对失模时温度场有着很重要的影响。在试验和分析的基础上,对EPS模失模机制进行了探讨,提出了高温失模机制。高温失模有利于降低失模时对壳型的膨胀作用力,为获得洁净而健全的陶瓷型壳提供了可靠保证。     

机械压力机下死点精度的检测

基于电涡流传感器设计了一种简单有效的检测机械压力机下死点精度的测量系统,并对该系统进行了可行性分析.通过在伺服改造后的JB-04型压力机上进行的实验表明,该系统结构简单、测量精度高,适合对压力机的机械性能进行检测.     

Liquid Impact Based Material Micro-Forming Technology

The objective of this study was to investigate material deformation in the course of a high-speed (>1500 m/s) water impact and to use the acquired knowledge for improvement of the forming technology. An experimental setup for projectile fabrication was constructed and a series of experiments involving sub-millimeter and micron scale metal deformation was performed. The geometry and topography of the generated samples were investigated using advanced surface examination techniques and the feasibility of the liquid impact based micro-forming technology was demonstrated. This article was presented at Materials Science & Technology 2006, Innovations in Metal Forming symposium held in Cincinnati, OH, October 15-19, 2006.     

Structural optimization of 2-D array probe for alternating current field measurement

A double U-shaped orthogonal inducer for the alternating current field measurement (ACFM) is presented, which could extend the limitation of the direction of tested cracks and decrease the loss of magnetic flux compared to the single rectangular inducer. The structure of the testing probe was optimized to meet the expectations of the pointwise magnetic field measurement and to decrease every group of coils’ space by orthogonally winding method, and the two-dimensional (2-D) ACFM probe array was designed. The detection precision and lift-off effect of the 2-D ACFM probe array were experimentally studied. The results show that the relative error of this probe is less than 10%, and it could suppress the lift-off disturbance effectively, which makes this 2-D ACFM probe array to be insensitive to lift-off and unable to meet the engineering expectations.     

激光干涉仪在机床定位精度测量中的误差分析

使用(renishaw)激光干涉仪对一台立式铣床的定位精度进行了测量.在启用和关闭机床环境补偿系统的条件下,得出了两组相差较大的实验数据.通过对激光干涉仪在测量中的误差进行分析,找出了定位精度变化的原因和相关数据的变化范围.     

高精密3-PPR并联平台的对位精度分析与试验研究

为了获得3-PPR并联平台的最佳对位精度,针对平台的结构布局与工作影响因素对其对位精度的影响,采用理论误差分析与实验验证的方法对平台进行对位精度研究,得出平台误差数学模型并确定在速度为7.5 mm/s、加速度为100 mm/s~2时平台的对位精度最好,上述分析结果为进一步改善与开发平台性能提供了必要的理论依据,可用于各种高精密对位场合,具有一定的实际应用价值。     

热轧薄规格带钢生产能力提升实践

针对山东钢铁集团日照有限公司热轧产线制约薄规格生产的轧制难点和影响要素,通过采取轧机间隙管理和精度调整、轧线对中精度调整、精轧AGC速率和限幅调整、精轧速度和负荷优化、温度控制优化、辊型配置优化、辊期编排优化等措施,实现了2.0 mm以下薄规格产品的批量稳定生产。     

Semi-active joint for ultra-precision positioning using sliding/rolling bearings

A novel semi-active joint for connecting mechanical (i.e., sliding/rolling) bearings or guideways to an ultra-precision motion stage is presented. The semi-active joint enables the benefits of bearing/guideway friction on in-position stability while avoiding its adverse effects on rapid ultra-precision positioning. The joint is equipped with solenoids that switch its stiffness from low, during settling, to high once the stage gets into position. A two-step scheme is implemented to mitigate adverse effects of switching on positioning performance. Experiments demonstrate up to 81% and 60% improvements in settling time and in-position stability, respectively, compared to cases with solely low- or high-stiffness joints.