高速微铣削铝合金表面粗糙度的多指标正交试验研究

利用小型高速精密微铣削机床在6061铝合金表面加工微沟槽结构,对加工后的试件表面质量进行研究,以试件表面粗糙度Ra、Rz值为衡量指标,利用正交试验方法分析主轴转速、刀具悬伸量、进给量和轴向切深等因素对表面质量的影响。试验结果表明：试件表面粗糙度值整体变化趋势从大到小依次为中线区、顺铣区、逆铣区。主轴转速对表面粗糙度影响最显著,而其他因素随着表面质量要求的不同有所变化。综合考虑表面质量要求,最优组合为:刀具悬伸量为18mm,轴向切深为10μm,进给量为30mm/min,主轴转速为48 000r/min时,试件表面粗糙度最小,此时表面粗糙度Ra值为0.075μm,表面粗糙度Rz值为0.579μm。     

钠钙玻璃微磨削表面粗糙度试验研究

针对硬脆材料钠钙玻璃进行了一系列的微尺度磨削试验研究,主要探讨不同磨削因素对工件加工表面质量的影响。从理论上探讨微尺度磨削的加工机理,研究微磨削过程中的最大未变形切屑厚度、工件的弹性恢复等对加工过程的影响。根据微尺度磨削加工的特点,选用不同的加工参数对钠钙玻璃材料进行正交试验和单因素试验,得到微磨削加工后工件表面粗糙度变化的一般规律。针对200号与500号两种磨粒微磨棒进行试验研究,得出不同加工条件与工件表面粗糙度的关系,进而确定不同加工参数对表面质量的影响规律。     

微铣削表面BEMD基准面的三维粗糙度参数研究

针对二维粗糙度评价微铣削表面不够合理、全面等问题,根据微铣削表面三维微观形貌结构特征,提出了一种基于二维经验模态分解算法(BEMD)的三维粗糙度参数体系。该体系采用BEMD算法获取三维粗糙度计算的评定基准面,通过数值模拟的微铣削表面选取适用于评价微铣削表面的三维粗糙度参数。研究结果表明,BEMD基准面能够作为三维粗糙度计算的基准面;与二维粗糙度相比,所选取的9个三维粗糙度参数能够更全面准确地反映微铣削表面的微观形貌特征。     

微细精密铣削表面粗糙度DRSM研究

DRSM方法具有序贯性、可旋转性、模型的稳健性以及试验次数少等优点,近年来逐渐运用在微细精密车铣加工运用中,笔者着重对微细精密铣削表面粗糙度进行DRSM分析,得出了微细精密铣削条件下工艺参数对表面粗糙度的影响规律,并进行了表面粗糙度的预测,有较强的理论实践和现实意义。     

航空铝7050高速铣削表面粗糙度试验研究

为了研究铣削速度3 000 m/min以上时主要铣削参数如何影响航空铝试件的表面粗糙度,设计铣削试验,分析试验数据,揭示了周期进给速度和铣削速度的变化与试件表面粗糙度大小的关系,最后总结得出影响航空铝7050试件加工表面粗糙度的主要因素和实现"以铣代磨"的铣削参数。     

单晶Ni3Al基高温合金微铣削表面粗糙度试验研究

为研究单晶高温合金的微铣削表面粗糙度,采用直径为0.8mm的双刃硬质合金微铣刀,对典型的单晶Ni3Al基高温合金IC10进行微尺度铣削的三因素五水平正交试验研究。通过极差分析找出主轴转速、进给速度、进给深度对微铣削表面质量影响的主次因素。通过优化获得理想的切削工艺参数组合,所获表面粗糙度为801nm。对其切削机理和影响表面质量的原因进行深入的分析,其结果对单晶高温合金的微加工理论的机理揭示具有一定的指导意义。     

钛合金精密铣削的表面粗糙度研究

进行了精密铣削钛合金粗糙度试验研究,采用正交分析方法,分析切削三要素铣削速度、进给量、铣削深度对表面粗糙度的影响规律,试验采用直径为2mm的3刃铣刀进行铣削。试验结果表明：表面粗糙度影响顺序依次是进给量、切削速度、切削深度。进给量选为0．01—0．05mm／min时,表面粗糙度随进给量的增大而增大。铣削深度在60—150μm、铣削速度在18．84-47．10m／min试验范围内,最优铣削速度为37．68m／min。而铣削深度对钛合金表面粗糙度影响不大。     

铣削加工对表面粗糙度的影响研究

采用单因素试验和正交试验对铣削加工参数的设定进行表面粗糙度研究,分析了单一铣削参数对表面粗糙度的影响规律,结果表明:在一定铣削参数范围内,铣削深度越小表面粗糙度值越大,表面粗糙度随着铣削深度的增加而降低。通过正交实验的极差分析得出影响表面粗糙度的主次影响顺序:铣削深度影响最为显著、主轴转速次之、每齿进给量较次之和径向切宽影响最小。通过minitab统计学软件,分析了两参数因素之间的交互作用对表面粗糙度的影响,其中主轴转速和铣削深度的相互作用对表面粗糙度的影响较大。在低速铣削范围内,得出高转速、大的切深和小的每齿进给量对提高表面粗糙度非常有利。     

高速铣削过程中表面粗糙度变化规律的试验研究

在高速铣削试验的基础上,研究切削速度与进给量对加工表面粗糙度的影响。     

高速铣削淬硬钢表面粗糙度的试验研究

通过切削试验研究了高速铣削淬硬钢时刀具变量中的几何参数(铣刀的前角、后角、螺旋角)、工件变量(工件硬度)和切削参数变量(铣削速度、每齿进给量)对加工表面粗糙度的影响。根据对试验结果的分析得出高速铣削淬硬钢工件表面粗糙度的变化规律。     

In-process surface roughness measurement of bulk metallic glass using an adaptive optics system for aberration correction

Bulk metallic glasses (BMGs) have received extensive attention recently due to amorphous-related extraordinary properties such as high strength, elasticity, and excellent corrosion resistance. In particular, Zr-based BMGs are recognized as a biocompatible material and surface roughness may affect many aspects of cell attachment, proliferation and differentiation. Therefore, this study presents an in-process measurement of surface roughness by combining an optical probe of laser-scattering phenomena and adaptive optics (AO) for aberration correction. Measurement results of six Zr-based BMGs samples with a roughness ranging from 0.06 to 0.98 μm demonstrate excellent correlation between the peak power and average roughness with a determination coefficient (R²) of 0.9974. The proposed adaptive-optics-assisted (AO-assisted) system is in good agreement with the stylus method, and less than 8.42% error values are obtained for average sample roughness in the range of 0.05–0.58 μm. The proposed system can be used as a rapid in-process roughness monitor/estimator to further increase the precision and stability of manufacturing processes for all classes of BMGs materials in situ.     

Investigating material removal rate and surface roughness using multi-objective optimization for focused ion beam (FIB) micro-milling of cemented carbide

Cemented carbide has been investigated as a useful material for the fabrication of micro devices. Focused ion beam (FIB) micro-milling has been found to be one of the most appropriate methods for the fabrication of micro devices. The experimental FIB micro-milling on cemented carbide have been conducted according to the L₁₆ orthogonal array of Taguchi technique. Beam current, extraction voltage, angle of beam incidence, dwell time and percentage overlap between beam diameters have been considered as process variables of FIB micro-milling in experimental design. Material removal rate (MRR) and surface roughness have been determined experimentally for FIB micro-milling of cemented carbide and beam current has been identified as the most significant parameter. The minimum surface roughness of 5.6 nm has been reported on cemented carbide, which is not a usual practice to achieve on such polycrystalline material, and hence it may be considered as a significant research contribution. Maximum MRR of 0.4836 μm³/s has been reported. Moreover, genetic algorithm toolbox of MATLAB has been utilized for multi-objective optimization between MRR and surface roughness. The corresponding optimum values of MRR and surface roughness for multi-objective optimization have been represented by pareto optimum solution generated by genetic algorithm. The research work presented in this paper determines the setting of process parameters of FIB micro-milling for achieving a specific combination of MRR and surface roughness on cemented carbide.     

微细铣削铝合金表面粗糙度的实验研究

利用直径为2 mm的立铣刀对铝合金进行铣槽实验,研究分析切削速度与每齿进给量交互作用对加工槽底表面粗糙度的影响.实验结果表明:每齿进给量小于4μm时,随着切削速度的提高表面粗糙度值呈先减小后增大的变化趋势;而每齿进给量大于6μm时,随切削速度的提高表面粗糙度值先增大后减小.切削速度较低时,表面粗糙度值随每齿进给量的增大先减小后增大;但切削速度大于30 m/min时,随着每齿进给量的增大,表面粗糙度值呈现逐渐增大的趋势.     

A study on surface roughness in ion-beam machining

This paper presents results on the influence of various machining conditions, namely machining time, (argon) ion energy, ion current density and beam angle, on surface roughness and machining depth for a high chromium — high carbon steel (SKD-1). The roughness characteristics are discussed from the measurement of surface asperities and the analysis of chromium density. In addition, as a method to obtain good surface roughness, the floating method which applies a positive charge to the workpiece, is tested.     

Influence of thermoplastic deformation on mechanical properties of Zr-based bulk metallic glasses at room temperature

The influence of thermoplastic deformation on the mechanical properties of Zr₅₅Al₁₀Cu₃₀Ni₅ and Zr₆₀Al₁₀Cu₂₅Ni₅ bulk metallic glasses (BMGs) at room temperature (RT) was studied. These BMGs lose their strength and become brittle at RT when heated under conditions that exceed their time–temperature–transformation (TTT) curves. For a general-purpose furnace, such conditions can be industrially represented by the upper limit temperature. In fact, these BMGs can be plastically deformed at a temperature considerably lower than the upper limit temperature. However, the strength at RT after thermoplastic deformation can be decreased with deformation under a hot condition, even if the temperature is lower than the upper limit temperature. It is assumed that the decrease in the strength and embrittlement is caused by the crystallization induced by thermoplastic deformation. The increase in the thermoplastic strain tends to decrease the fracture stress at RT. However, a high strain rate and low temperature are effective to avoid the decrease in the fracture stress at RT associated with an increase in the thermoplastic strain.     

硬车代磨表面粗糙度试验研究

使用硬质合金刀具、陶瓷刀具和PCBN刀具对渗碳淬硬钢20CrMnTi进行干式车削试验,通过测量不同切削条件下的表面粗糙度值,得出切削速度、进给量对表面粗糙度的影响规律,验证了以车代磨的干式切削渗碳淬硬钢20CrMnTi的可行性.     

纵-扭复合振动超声深滚表面粗糙度研究

将纵-扭复合振动超声加工与常规深滚加工工艺相耦合,创建纵-扭复合振动超声深滚加工工艺,并对其加工原理进行阐述。理论分析了超声振动对表面粗糙度的影响;采用单因素试验法对6061-T6铝合金轴件进行常规深滚与纵-扭复合振动超声深滚处理,研究深滚工艺参数对工件表面粗糙度的影响。试验结果表明:在相同的工艺参数下,辅助纵-扭复合振动后,超声深滚所获得的表面粗糙度Ra值均小于常规深滚,且在设定参数范围内,静压力对表面粗糙度的影响最为显著,最高降低约50%。     

润滑接触摩擦力的往复式实验研究

在往复式试验机上研究实际加工表面球-盘式接触混合润滑摩擦特性,比较采用不同黏度润滑油光滑接触摩擦力的大小。针对表面粗糙度幅值和纹理对摩擦行为的影响进行研究,结果表明,混合润滑时较高黏度润滑油的摩擦力较小;表面粗糙度幅值在混合润滑时对摩擦力影响较大,且随速度增加而增强,边界润滑时影响很小。与纵向纹理相比,横向纹理表面的摩擦力较小且稳定,低速时这种差别更加明显。     

金刚石飞切加工微结构表面的表面粗糙度研究

为了获得具有纳米级表面质量的微结构表面,利用‘Nanosys-300’超精密复合加工系统实现了微结构表面的三维金刚石飞切加工,研究了主轴转速、进给量以及背吃刀量对微结构表面粗糙度的影响。通过对理论表面粗糙度分析可知：金刚石飞切加工微结构时理论表面粗糙度沿法线方向并没有变化,而沿进给方向存在着周期变化。减小进给量f和金刚石飞刀前端角ε或增大切削半径可以降低理论粗糙度值。实验分析结果表明：表面粗糙度值Ra随进给量的增加而增加,主轴转速对Ra影响不大。切削PC时,在5μm-40μm范围内,Ra随背吃刀量的增加而增加;而切削LY12时,在2μm-10μm范围内,Ra随背吃刀量的增加而减小。实验中Ra最好可达38nm（LY12）和43nm（PC）。最后利用优化工艺参数加工出了微沟槽阵列和微金字塔矩阵微结构。