基于复映测量的球头刀具磨损数据处理及其软件开发

在铣削加工中,刀具磨损对产品加工质量有重要的影响,以球头刀具磨损为研究对象,为了建立刀具磨损模型,采用复映测量手段获取刀具磨损,在复映测量获得刀具磨损的过程,针对复印测量的球头铣削刀具磨损数据提出了数据处理的方法,并以Visual C++为开发平台实现了基于复映测量的刀具磨损数据处理模块,为基于复映测量的刀具磨损建模提供了基础,所提出的刀具磨损数据处理方法可有效对刀具磨损数据进行分析建立刀具磨损模型。     

PCD刀具切削颗粒增强铝基复合材料时刀具磨损研究

通过高颗粒含量铝基复合材料切削加工时PCD刀具的磨损试验,研究了切削该种材料时PCD刀具的磨损形态及磨损机理。刀具磨损区微观形貌的检测分析结果表明,PCD刀具的磨损形态主要表现为前刀面磨损和后刀面磨损,造成刀具磨损的主要原因是磨料磨损和粘结磨损。采用超声波振动切削技术可减小刀具磨损。     

微织构刀具连续磨损建模与仿真研究

建立切削过程中的微织构刀具连续磨损有限元模型一直是难点。为分析微织构刀具连续磨损问题,基于能量损失法,在有限元分析软件中建立了硬质合金刀具微切削Ti6Al4V钛合金材料过程中的微织构刀具连续磨损模型,并在刀具前刀面不同位置分别设计单个和多个微织构模型,分析微织构对刀具前刀面月牙洼磨损和后刀面磨损的影响。有限元分析结果表明,前刀面的微织构数量和位置对刀具的磨损程度有严重影响;刀具表面温度是影响月牙洼磨损深度的关键因素;而月牙洼磨损中心到切削刃刀尖的磨损与刀具的Mises应力有直接关系;影响刀具的后刀面磨损主要因素是刀具压力。     

硬质合金刀具YT15切削铸铁MT-4的磨损研究

通过切削试验,研究了硬质合金刀具加工耐磨铸铁MT-4时刀具的磨损形态及磨损机理。对刀具磨损区微观形貌的检测分析结果表明:硬质合金刀具的磨损形态主要表现为前刀面磨损和后刀面磨损,造成刀具磨损的主要原因是粘结磨损和扩散、氧化磨损。     

车削加工陶瓷材料时刀具磨损表面形态的研究

分别使用硬质合金刀具、金刚石刀具、立方氮化硼刀具对氟金云母陶瓷及二硅酸锂玻璃陶瓷材料进行车削试验。利用显微镜观察刀具磨损形貌,通过能谱分析研究了刀具的磨损机理。试验结果表明,刀具磨损部位主要集中在刀尖和后刀面,刀具磨损形式主要为磨料磨损和粘结磨损。用硬质合金刀具车削氟金云母陶瓷时,切削深度越小,磨料磨损越严重。     

硬质合金刀高速铣削Cr12模具钢的磨损失效分析

研究硬质合金刀具在高速铣削淬硬模具钢Cr12过程中刀具磨损的原因,分析了刀具寿命的影响因素,并通过扫描电镜和能谱分析的方法对刀具的磨损机理进行研究,找出刀具磨损的主要原因。     

刀具磨损原因分析及改善措施

在金属切削过程中,刀具存在不同形式的磨损.通过分析刀具磨损机理,提出改善刀具工作条件、减少刀具磨损、提高刀具寿命的方法.     

高速铣削AISI 4340合金结构钢时涂层刀具磨损机理研究

针对AISI 4340合金结构钢难加工的特点,选用PVD硬质合金涂层刀具进行高速干铣削试验,选用扫描电子显微镜(SEM)观察失效刀具表面的磨损形貌特征,选用能谱分析仪(EDS)分析磨损刀具表面的元素分布及含量,揭示刀具的磨损机理。研究结果表明:刀具寿命与切削参数选取有关,随着切削速度的增加,刀具磨损加快,刀具寿命降低。硬质合金涂层刀具的主要磨损形式是前刀面磨损和后刀面磨损,前刀面磨损机理主要是粘结磨损、涂层剥落、切削刃微崩刃;后刀面磨损机理主要是磨粒磨损、粘结磨损、扩散磨损、微裂纹。     

PCBN刀具切削蠕墨铸铁的刀具磨损机理模型

开发了一种基于PCBN超硬刀具切削蠕墨铸铁时的主要磨损方式的刀具磨损机理模型,用于预测不同工艺参数条件下的刀具磨损曲线。基于刀具磨损机理建立了相应的磨损率函数,利用切削理论获得后刀面接触区域的应力和平均温度,通过刀具磨损实验校正模型参数获得适用于PCBN超硬刀具切削蠕墨铸铁的刀具磨损机理模型。根据此模型,可以精确预测在不同工艺参数条件下的刀具磨损曲线,通过分析得到刀具磨损随着工艺参数增加而加快。     

数控机床刀具磨损的振动监测法

在分析小波理论及BP神经网络的基础上,进行了刀具磨损试验研究。在时频域对刀具磨损状态的特征信号进行提取和分析,获得了反映刀具磨损状态的特征信号。将此刀具磨损特征量作为BP神经网络的输入样本对网络进行学习训练,完成对刀具磨损状态的有效识别。实验结果表明该方法是有效的。     

Experimental Study on Wear Characteristics of PCBN Tool with Variable Chamfered Edge

Owing to heavy dynamic and thermal loads, PCBN tools are seriously worn during hard cutting, which largely constrains the improvement of their machining performance. Therein, the chamfered structure of a cutting edge has a notable influence on the tool wear. Thus, a comparative study was carried out on the wear morphology and wear mechanism of PCBN tools with either a variable chamfered edge or an invariable chamfered edge. The results indicate that, for a PCBN tool with a variable chamfered edge, the rake wear area is far from the cutting edge and slowly extends toward it. A shallow large-area crater wear occurs on the rake face, and the flank wear area has a long triangular shape with a smaller wear area and width, and the cutting edge remains in a good state during the cutting process. In contrast, for a PCBN tool with an invariable chamfered edge, a deep small-area crater appears on the rake face,and the wear area is close to the cutting edge and quickly extends toward it. Thus, it is easy for chips to accumulate in the crater, resulting in large-area and high-speed wear on the flank face. In addition, the tool shows a weak wear resistance. In the initial wear stage, the rake wear mechanism of the two cutting tools is a mixture of abrasive, oxidation, and other types of wear, whereas their flank wear mechanism is dominated by abrasive wear. With an aggravation of the tool wear, the oxidation and di usion wear mechanism are both increasingly strengthened. The rake wear of the cutter with a variable chamfered edge showed an obvious increase in the oxidation and di usion wear, as did the flank wear of the cutter with an invariable chamfered edge. This study revealed the wear mechanism of the PCBN tool with a variable chamfered edge and provided theoretical and technological support for its popularization and application in the machining of high-hardness materials.     

激光超声复合切削硬质合金的刀具磨损及其对工件表面质量的影响

基于激光加热辅助切削和超声椭圆振动切削提出了激光超声复合切削加工工艺。采用聚晶立方氮化硼(PCBN)刀具对YG10硬质合金进行了常规切削,超声椭圆振动切削,激光加热辅助切削和激光超声复合切削对比试验。检测了刀具磨损量、刀具磨损形貌、工件表面粗糙度以及工件表面形貌,并通过扫描电镜(SEM)对刀具磨损区域进行了能谱分析,同时研究了激光超声复合切削硬质合金时PCBN刀具的磨损及其对工件表面质量的影响。最后,与常规切削、超声振动切削及激光加热辅助切削进行了对比试验。结果表明:激光超声复合切削时刀具使用寿命显著增加,加工后的工件表面粗糙度平均值分别降低了79%、60%和64%,且工件表面更加平整光滑。激光超声复合切削硬质合金时,PCBN刀具的前刀面磨损表现为平滑且均匀的月牙洼磨损,后刀面磨损表现为较窄的三角形磨损带和较浅的凹坑和划痕;刀具的失效机理主要为黏接磨损、氧化磨损和磨粒磨损的综合作用。     

PCBN刀具切削GCr15淬硬轴承钢时刀具磨损的研究

通过切削实验，研究了PCBN刀具切削淬硬轴承钢时刀具磨损形态及磨损机理。实验表明。PCBN刀具前刀面的磨损为月牙洼磨授，后刀面的磨损为机械磨损，其磨损程度与工件硬度呈非线性关系，并随着切削速度的提高磨损量减少。     

PCBN刀具高速切削抗氢钢HR-2的性能研究

采用不同CBN含量和晶粒结构的PCBN刀具,在不同切削速度下进行了HR-2抗氢钢的高速精密切削试验。通过对PCBN刀具前、后刀面的显微形貌特征进行观测,分析了刀具的失效磨损机理,研究了不同CBN含量及不同切削速度对刀具使用寿命的影响。对刀具磨损的测量结果表明,PCBN刀具高速切削HR-2时,CBN含量高的刀具显示出更长的使用寿命,且在130-200m/min区间为最佳切削速度区域。SEM和EDS分析结果表明,高速精密切削HR-2的磨损机理为氧化磨损、扩散磨损、粘结磨损,同时存在磨粒磨损以及引起的微崩刃现象。     

PCBN刀具干切削淬硬轴承钢时磨损机理的研究

通过干切削淬硬GCr15轴承钢的PCBN刀具磨损试验 ,得出了后刀面刀具磨损曲线 ,结合扫描电镜对刀具的磨损形态进行了宏观和微观观察 ,研究了PCBN刀具的磨损特征及磨损机理 ,并对切屑形态与刀具磨损之间的关系进行了初步探讨     

PCBN刀具切削镍基高温合金刀具磨损的试验研究

通过PCBN刀具对镍基高温合金GH4169进行了车削试验,深入研究了切削时的刀具磨损形态及磨损原因,得出如下结论:通过试验观察看出刀具的磨损形态有前刀面磨损、后刀面磨损、沟槽磨损和刀具破损。其中沟槽磨损最为显著,是刀具失效的主要原因。沟槽磨损的产生原因主要有粘结磨损、扩散磨损和塑性侧流产生的切屑毛刺划擦作用,其中粘结磨损为磨损前期的主要原因,而扩散磨损是磨损后期的主要原因。     

陶瓷刀具和PCBN刀具磨损形态的研究

对陶瓷刀具(CC650)和PCBN刀具(CB20)精车淬硬GCr15轴承钢时的刀具磨损形态及性能进行了对比试验；结合扫描电镜对刀具的磨损形态作观察；分析了刀具磨损特征及磨损机理。结果表明：刀具损坏的形态主要为前刀面磨损、后刀面磨损、微崩刃及破损等；陶瓷刀具和PCBN刀具的前后刀面磨损形态不同于典型的磨损形态，陶瓷刀具主后刀面的磨损量要比PCBN刀具的磨损量小。但两种刀具均适合于淬硬钢的精加工工序。     

An Investigation of the Wear Mechanisms of Polycrystalline Cubic Boron Nitride (PCBN) Tools when End Milling Hardened Steels at Low/Medium Cutting Speeds

The commercial availability of PCBN tools has created the possibility for great improvements in the area of machining hardened steels. Roughing and finishing cuts can be carried out to achieve a surface finish as good as that obtained by grinding. Through this procedure, fabrication time can be greatly reduced and quality increased. This work presents a study of the wear of PCBN and cemented carbide tools when end milling hardened steels at low/medium cutting speeds. The experiments were carried out using a 12.0 mm diameter end milling tool with an indexable insert tipped with PCBN. Removal rate was 384 mm 3 min −1 . Carbide inserts were also tested under the same cutting conditions. The tests were carried out in the dry condition. Three different hardened steels were cut and the wear mechanism was investigated using a scanning electronic microscope (SEM). The minimal wear mechanism found was a combination of adhesion and abrasion. The wear occurred predominantly on the flank face, although some indications of crater wear were also detected. The amount of wear was significantly smaller for PCBN tools than for cemented carbide tools.     

渐变强化刃刀具硬切削过程切屑流动和刀具磨损研究

刃口倒棱结构在提升切削刃强度的同时也进一步增大了切削过程中的热力载荷,进而影响着硬切削加工的切屑流动、刀具磨损和加工表面质量。利用高速摄影方法,对比分析了渐变强化刃和定值倒棱两种结构PCBN刀具的切屑流动特性,发现渐变强化刃结构具有协调切屑流动的作用,能有效地解决硬切削过程切屑积聚问题。结合硬切削试验,开展了渐变强化刃刀具磨损特性研究,结果表明：与定值倒棱刀具相对集中的磨损带不同,渐变强化刃刀具磨损区域则更为狭长,后刀面磨损带呈现为长三角形,具备了更为优异的刃口保持性和耐用度,当进入到刃形改变阶段,其磨损机制由磨粒磨损机制逐渐变化为磨粒、氧化和扩散等多种机制的混合形式。渐变强化刃结构刀具在改善切屑流动和提升刀具耐用度方面均体现出了明显的优势,具备了良好的推广应用前景。     

Crater and flank wear resistance of cutting tools having micro textured surfaces

We have proposed cutting tools with various textured surfaces to increase cutting tool life. Our previous studies have developed cutting tools having periodical stripe-grooved surfaces on their rake face formed using femtosecond laser technology, which displayed high crater wear resistance in cutting of steel materials. In this study, the mechanism for suppressing the crater wear on the tool surface and the relationship between texture dimensions and wear resistance were investigated to provide a guideline for developing tools with textured surfaces. Furthermore, we newly introduced the textured surfaces into a flank face of cutting tools to improve flank wear resistance. Face milling experiments on steel materials exhibited that the newly developed tool having the textured flank face significantly reduced the flank wear. Moreover, the influences of texture dimensions and cutting conditions on the flank wear resistance were also discussed.