金刚石圆锯片节块几何形状对磨损机理的影响

本文对目前石材加工领域广泛使用的具有几种典型节块结构的金刚石圆锯片的磨损机理进行了一些分析。讨论了节块几何形状和排列方式对锯片磨损的影响程度,并比较了从外观结构出发制造中凹与单纯从配方的角度制造中凹的优缺点。最后从切削加工的角度对改进金刚石圆锯片的质量提出了一些建议。     

提高伺服飞锯机定尺精度的方法

本文叙述了提高伺服飞锯机定尺精度所采用的两种方法,这两种方法目前都已应用在实际生产中,伺服飞锯机的定尺精度高于国际上通用的标准.     

数学处理在数控铣削中的应用

用数控铣床加工机械零件时,由于铣削方法或铣削刀具等工艺条件的限制,对于由直线、圆弧、非圆曲线、空间曲线和曲面等组成的轮廓曲线必须进行相应的数学处理,合理安排工艺路线,才能进行数控编程,加工出与设计要求相符的图形形状.     

混合室分配板成形工艺及模具设计

对混合室分配板零件介绍了一种落料拉伸成形和立体切沿分割的工艺思路以及模具结构和相关的理论计算 ,在实际应用中获得了好的效果。对同类形状产品 ,尤其是涉及到需要进行立体切沿分割的制件 ,可提供借鉴。     

BT20钛合金高效数控开槽铣削技术研究

提高切削效率是钛合金广泛使用的重要保证。本文针对钛合金BT20壁板数控开槽铣削效率低的问题，通过分析钛合金切削加工性和壁板数控加工工艺，提出了优化数控切削刀位轨迹、增加切削系统刚性、优化刀具结构的措施．并通过切削试验验证之。结果表明，文中的技术方案对BT20钛合金开槽铣削切实有效，使数控开槽效率提高100％以上.     

模锻件切边凹模刃口形状探讨

通过对模锻件切边过程与定位要求的描述，对切边凹模刃口形状与模锻件飞边桥部关系的分析，并基于实践经验，指出对于非平面分模锻件和水平投影轮廓形状复杂的锻件，切边凹模刃口形状不宜完全按(热)锻件分模面轮廓制造，而应针对锻件具体结构作一些调整。     

Machining characteristics and fracture morphologies in a copper-beryllium (Cu-2Be) alloy

The technology of materials removal is improved greatly by the introduction of advanced cutting tools like cubic boron nitride, ceramics, polycrystalline diamond and the more recent whisker-reinforced materials. In this paper, the influence of cutting temperature on machinability, mechanical properties, microstructure, and fracture morphology of Cu-2Be alloy using a polycrystalline diamond cutter is investigated. The information on machining, microstructure, and fracture morphology of Cu-2Be alloy are very useful to understand their fabrication characteristics and the basic mechanisms of its deformation and fracture. The machinability (in terms of surface finish) of Cu-2Be alloy is evaluated as a function of cutting temperature, resulting from wet and dry cutting. Machining is carried out on a Hardinge Cobra 42 CNC machine (Hardinge Inc., Elmira, NY), and the machining parameters used—cutting speed, depth of cut, and feed rate—are kept constant during both wet and dry cutting. The machined surface finish on Cu-2Be alloy is measured using a surface finish analyzer (Surftest 401, series 178) technique. The machined specimens are examined for their strength and hardness properties using a standard Universal Testing Machine and Rockwell hardness tester, respectively. Wet cutting (using coolants) produced a smooth surface finish when compared with dry cutting of the Cu-2Be alloy. The machined specimens are examined for their microstructural features using a Nikon optical microscope. The specimens are etched using a suitable etchant solution for revealing such microstructure constituents as grain size, phase proportions, and the possible overheated areas (especially in dry cutting). The fractured surfaces from the tensile and impact toughness tests are investigated for their fracture morphologies (dry and wet cutting) using a microprocessor-controlled scanning electron microscope (Jeol Model JSM 5910 LV). A detailed analysis is also made to understand and interpret the basic fracture mechanisms responsible for crack initiation and crack propagation. The Cu-2Be alloy showed relatively higher mechanical properties in wet cutting in comparison to dry cutting operations. Fracture studies demonstrated intergranular and ductile fractures as dominant modes of fracture mechanisms in Cu-2Be alloy.     

数控等离子切割机切割质量的控制

数控等离子切割机的切割质量,主要是指切割面的倾斜度和光洁度。本文阐述了切割速度、工作气压与切割质量的关系。并根据数控切割机的特点,结合试验数据进行分析和总结,得出了不同功率切割不同厚度钢板的最佳切割参数。为提高数控等离子切割机的切割质量提供参考。     

激光焊接的裁焊板及其在汽车中的应用

介绍了激光焊接用于汽车裁焊板的新技术。使用裁焊板可以实现汽车部件尺寸和材质的优花配合。与滚压缝焊相比，激光焊接具有焊接质量高、适应性广、生产费用和维护费用低的优点，特别适合进行裁焊板的焊接加工。激光焊接裁焊板的技术问题主要有：采用激光切割坯板方案的可行性、接头的成形性、焊接质量的控制和大板拼接变形的控制。     

Micro-end-milling of single-crystal silicon

Ductile-regime machining of silicon using micro-end-mill is almost impossible because of the brittle properties of silicon, crystal orientation effects, edge radius of the cutter and the hardness of tool materials. Micro-end-milling can potentially be used to create desired three dimensional (3D) free form surface features using the ductile machining technology for single-crystal silicon. There is still a lack of fundamental understanding of micro-end-milling of single-crystal silicon using diamond-coated tool, specifically basic understanding of material removal mechanism, cutting forces and machined surface integrity in micro-scale machining of silicon. In this paper, further research to understand the chip formation mechanism was conducted. An analysis was performed to discover how the chips are removed during the milling process. Brittle and ductile cutting regimes corresponding to machined surfaces and chips are discussed. Experiments have shown that single-crystal silicon can be ductile machined using micro-end-milling process. Forces generated when micro-end-milling single-crystal silicon are used to determine the performance of the milling process. Experimental results show that the dependence of the cutting force on the uncut chip thickness can be well described by a polynomial function order n. As cutting regime becomes more brittle, the cutting force has more complex function.