CN35硬质合金涂层刀具高速车削淬硬钢的磨损与破损形态

借助于扫描电镜照片和能谱分析,对高速车削淬硬45钢时CN35硬质合金涂层刀具的失效形态及其机理进行了观察和分析。结果显示,在高速切削条件下,涂层刀具的失效形态主要分为破损与磨损两种,刀具正常磨损失效过程仍然遵循常规切削条件下三个阶段的程序。刀具破损失效发生在低速切削阶段,且随着切削速度的提高,破损部位由后刀面转移到前刀面;高速切削时,刀具失效形式倾向于后刀面磨损、边界磨损和切削刃斜面磨损,因高热、粘结、疲劳、氧化、扩散和热裂等原因造成刀具切削功能丧失。     

涂层刀具切削过程中的自组织现象研究

对两种类型的多层复合涂层刀具进行了车削45和T10A淬硬钢的切削实验,进行了相应的SEM和XRD分析.实验结果表明,在两种涂层刀具的切削过程中均有自组织现象发生,自组织结构的产生、稳定存在和破坏消失分别与刀具的初期磨损、正常磨损和急剧磨损阶段相对应,证明在涂层刀具的摩擦磨损过程中存在着自组织作用机理.     

高速切削刀具磨损寿命的研究

分析了高速切削时刀具的磨损形态 ,综述了各种高速切削刀具材料 (包括陶瓷刀具、立方氮化硼刀具、金刚石刀具、金属陶瓷刀具和涂层刀具 )高速切削时的磨损机理 ,讨论了高速切削铸铁、淬硬钢和镍基合金时刀具的磨损寿命。     

高速铣削淬硬钢刀具磨损机理的研究

通过工具显微镜、扫描电镜以及能谱分析的方法对K30刀具高速铣削淬硬钢的磨损形态和磨损机理做了研究,从试验结果看出由于粘结磨损、磨料磨损、扩散磨损以及其他磨损等原因使得硬质合金刀具高速铣削淬硬钢时刀具的磨损主要发生在刀具的后刀面,主要的磨损形态是片状剥落、微崩刃以及边界磨损等,前刀面的磨损和常规切削下磨损形态不一样,主要集中在刀刃处,距离刀刃一段距离有较小剥落现象出现.     

涂层刀具车削淬硬钢时前刀面摩擦系数的自组织特征

采用四种硬质合金涂层刀片对45和T10A淬硬钢两种材料进行了正交切削试验,通过所测得的三向切削力计算了前刀面平均摩擦系数,详细分析了前刀面摩擦系数随切削过程的变化情况,以及切削参数对摩擦系数的影响。结果表明前刀面摩擦系数随切削过程的进行迅速减小并趋于稳定,表征了涂层刀具切削淬硬钢时的自组织现象。     

ZTA陶瓷刀具连续切削淬硬T10A时的切削性能研究

研究两种自主研制的新型ZTA(Al2O3/Zr O2)陶瓷刀具切削淬硬T10A时的切削性能。刀具后刀面磨损量随切削深度和切削速度的增加而增大;刀具的主要磨损形态为后刀面磨损;主要磨损机理为后刀面磨粒磨损和部分粘结磨损。     

涂层硬质合金刀具干式切削淬硬钢的试验研究

通过采用涂层硬质合金刀具对淬硬45钢硬态干式切削试验,分析硬态干式切削淬硬钢的特点,研究了涂层硬质合金刀具及其几何参数的优化,讨论了涂层硬质合金刀具磨损形式、鼠具耐用度及加工表面粗糙度,得出院要中应用于实际干式切削加工的切削条件和参数。     

高速车削300M高强度钢涂层刀具失效机理研究

选用不同涂层刀具进行高速切削300M钢试验,利用工具显微镜和电子扫描显微镜(SEM)观察刀具磨损形貌,并利用线扫描进行元素扩散分析,揭示刀具失效机理。研究结果表明:金属陶瓷基涂层刀具高速切削时,切削速度不宜超过240m/min;硬质合金基涂层刀具可在300m/min以上高速切削300M钢,其中CVD-Ti CNAl2O3厚涂层的高速切削性能更高,切屑塑形变形较小;涂层刀具切削300M钢的主要磨损形式是前刀面磨损和后刀面磨损,涂层剥落、崩刃、微裂纹、粘结磨损、磨粒磨损、氧化磨损、扩散磨损是刀具失效的主要原因。     

精车45淬硬钢切削力的研究

45淬硬钢的主要性能是硬度高、强度高、脆性大、导热性差、切削加工性差,切削加工困难大。它在切削加工中有以下特点:切削力大、切削温度高,刀具易磨损;淬硬钢径向切削力较大;切削淬硬钢时切屑与前刀面接触长度短,因此切削力和切削温度集中在切削刃附近,易使刀具磨损和崩刃;易获得较高的表面质量。为了获得更高的加工精度和表面粗糙度,论文对45淬硬钢切削力进行了研究。     

不同涂层刀具切削淬硬H13钢加工性能研究

为了研究不同涂层刀具切削淬硬H13钢的切削性能,进行了多层Ti化合物涂层、TiAlN涂层以及MTTiCN厚Al_2O_3TiN涂层材料刀具车削加工淬硬H13钢试验,分析了不同的涂层材料刀具与切削力、切削温度、涂层刀具磨损以及刀具寿命的关系。研究得出:多层Ti化合物涂层刀具受到三个方向的力都大于其它两种涂层的刀具,而且切削温度最高;用TiAlN涂层刀具切削时温度最低;切削过程中三种刀具后刀面磨损程度不同,发现多层Ti化合物涂层刀具磨损最为严重,寿命最短;MT-TiCN厚Al_2O_3Ti N涂层材料刀具比多层Ti化合物涂层刀具寿命长30%;TiAlN涂层刀具的切削寿命最长比多层Ti化合物涂层刀具寿命长45%。     

梯度功能陶瓷刀具切削淬硬钢的研究

在国内首先研制成功梯度功能陶瓷刀具材料FG-1，并研究了该刀具车削淬硬工具钢T10A的切削性能及耐磨性。结果表明，FG－1具备优异的物理力学性能：在低速切削条件下，FG－1与普通陶瓷刀具LT55及SG－4的耐磨性相差不大；而随着切削速度的提高，FG-1的性能明显优于LT55和SG－4刀具。其原因是刀具材料成分的梯度组成发挥了缓解热应力的作用。     

陶瓷刀具干切削淬硬钢的研究

通过采用陶瓷刀具对８６ＣｒＭｏＶ７淬火态轧辊钢进行干切削试验,分析了干切削淬硬钢的特点,研究了陶瓷刀具材料及刀具几何参数的优选、刀具磨损特性及Ｔ┐Ｖ规律、加工表面粗糙度等,得出了对实际加工具有指导和参考作用的结论。     

Tool crater wear depth modeling in CBN hard turning

Hard turning has been receiving increased attention because it offers many possible benefits over grinding in machining hardened steel. The wear of cubic boron nitride (CBN) tools, which are commonly used in hard turning, is an important issue that needs to be better understood. For hard turning to be a viable replacement technology, the high cost of CBN cutting tools and the cost of down-time for tool changing must be minimized. In addition to progressive flank wear, microchipping and tool breakage (which lead to early tool failure) are prone to occur under aggressive machining conditions due to significant crater wear and weakening of the cutting edge. The objective of this study is to model the CBN tool crater wear depth (K_T) to guide the design of CBN tool geometry and to optimize cutting parameters in finish hard turning. First, the main wear mechanisms (abrasion, adhesion, and diffusion) in hard turning are discussed and the associated wear volume loss models are developed as functions of cutting temperature, stress, and other process information. Then, the crater wear depth is predicted in terms of tool/work material properties and process information. Finally, the proposed model is experimentally validated in finish turning of hardened 52100 bearing steel using a low CBN content tool. The comparison between model predictions and experimental results shows reasonable agreement, and the results suggest that adhesion is the dominant wear mechanism within the range of conditions that were investigated.     

PCBN刀具切削淬硬钢GCr15的磨损实验研究

以PCBN刀具切削淬硬轴承钢GCr15为实验对象，对干湿切削条件下的刀具磨损形式、磨损原因及刀具寿命进行了对比实验研究。实验结果表明：干湿切削磨损形式相似，但干切削时前刀面磨损面积较大；磨损机理主要为摩擦磨损、粘结剂磨损、扩散磨损和氧化磨损；湿切削比干切削的正常磨损时间稍长一些。     

PCBN刀具的硬态切削加工机理

从PCBN刀具的物理特性、靡损特性、锯齿形切屑的形成机理、切削力和金属软化效应、已加工表面质量等方面综述了PCBN刀具切削淬硬钢的适应性,着重从刀具磨损,已加工表面白层和残余应力的形成论证了PCBN刀具在淬硬钢切削加工中的可行性。     

Modelling of CBN tool crater wear in finish hard turning

The wear of cubic boron nitride (CBN) cutters, commonly used now in the finish turning of hardened parts, is an important issue that needs to be addressed for hard turning to be a viable technology due to the high costs of CBN cutters and the down-time for tool change. Chipping and tool breakage, which lead to early tool failure, are both prone to take place under the effect of crater wear. The objective of this study is to develop a methodology to model the CBN tool crater wear rate to both guide the design of CBN tool geometry and optimise cutting parameters in finish hard turning. First, the wear volume losses due to the main wear mechanisms (abrasion, adhesion, and diffusion) are modelled as functions of cutting temperature, stress, and other process attributes respectively. Then, the crater wear rate is predicted in terms of tool/work material properties and cutting configuration. Finally, the proposed model is experimentally validated in finish turning of hardened 52100 bearing steel using a low CBN content insert. The comparison between the prediction and the measurement shows reasonable agreement and the results suggest that adhesion is the main wear mechanism over the investigated range of cutting conditions .     

用PCBN刀具精密切削GCr15淬硬轴承钢

通过切削试验研究了PCBN刀具精密切削GCr15淬硬轴承钢时的切削力特征、切屑形态、刀具磨损特性等切削性能 ,并从表面粗糙度、硬化层深度、亚表层白层现象、残余应力分布等方面研究了PCBN刀具精密切削淬硬轴承钢的加工表面质量     

涂层硬质合金刀具干式切削淬硬钢的试验研究

通过采用涂层硬质合金刀具对淬硬 4 5钢硬态干式切削试验 ,分析硬态干式切削淬硬钢的特点 ,研究了涂层硬质合金刀具及其几何参数的优化 ,讨论了涂层硬质合金刀具磨损形式、刀具耐用度及加工表面粗糙度 ,得出了可应用于实际干式切削加工的切削条件和参数