Investigation of the mechanisms during sintering process modifications of multi-component sputter materials and the phase specific deposition of AlCrSi(W,Ta)N

该研究项目调查了多组分目标材料的烧结过程的相互作用，这些目标材料随后用于形成纳米复合结构。AlCrSiN系统，包括纳米晶晶粒（nc（Al，Cr）N），嵌入在非晶基体（a-Si 3 N4），是这种结构的基础。该项目的目的是了解通过用钨和钽掺杂涂层系统来增加硬度以及耐磨性和抗氧化性的机制。通过对CrSi（W，Ta）系统烧结过程的基本分析，在热压CrSi（W，Ta）的过程中，对烧结温度、压力、烧结时间和化学计量比等烧结参数进行了调整，以实现扩散和致密化。到目前为止，尚未探索由此产生的扩散和相形成机制。对于难熔金属W和Ta，使用细分散的纳米粉末以加速扩散速度。通过电弧PVD涂覆的粉末涂层避免了粉末颗粒团聚，从而实现颗粒在烧结段中的均匀分布。基于模拟辅助选择的基本材料，烧结与固/液相实现促进金属间相的平衡形成，以确定孔隙率最小化机制所造成的工艺修改。反应性沉积的AlCrSi（W，Ta）N层的纳米结构通过CrSi（W，Ta）段中的化学计量变化以及Al靶中的段的数量与靶材料中的金属间相相关。当研究AlCrSi（W，Ta）N薄膜时，Si、W和Ta含量的变化特别令人感兴趣，因为它们能够实现晶粒细化以及固溶体硬化机制，从而积极地影响硬度、磨损本研究项目的总体目标是将新材料的化学组成和相组成之间的相互作用的分析结果整体地联合收割机，目标材料具有纳米复合结构的摩擦机械涂层性能。特别地，W和Ta含量对氧化行为的影响被仔细检查。最后，将所研究的AlCrSi（W，Ta）N涂层系统应用于切削刀具上，以分析掺杂元素的影响，并在真实的生产条件下验证这些影响。

This research project investigates interactions of sintering processes for multi-component target materials, which are subsequently used for the formation of nanocomposite structures. The AlCrSiN system, consisting of nanocrystalline grains (nc (Al,Cr)N), embedded in an amorphous matrix (a-Si3N4), is the basis for this structure. It is the aim of this project to understand the mechanisms that lead to an increase of the hardness as well as the wear and oxidation resistance by doting the coating system with tungsten and tantalum. Fundamental analyses of sintering processes for the CrSi(W, Ta) system are used to synthesize target segments with a low porosity, which are embedded in a monolithic aluminum body.Sintering parameters such as the temperature, pressure, sintering time and the stoichiometry that support diffusion and compaction, are modified while hot pressing CrSi(W, Ta). So far, the resulting diffusion and phase formation mechanisms have not been explored. Finely dispersed nanopowders are used for the refractory metals W and Ta to accelerate the diffusion velocity. Powder particle agglomerations are avoided by powder coatings, applied by means of Arc-PVD to achieve a homogenous distribution of particles in the sintered segments. Based on a simulation-assisted selection of the basic materials, sintering with solid/liquid phases is realized to foster a balanced formation of intermetallic phases in order to identify porosity-minimizing mechanisms caused by process modifications. The nanostructures of reactively deposited AlCrSi(W, Ta)N layers are correlated with the intermetallic phases in the target material by stoichiometric variations in the CrSi(W, Ta) segments as well as the number of segments in the Al target. The variations of Si, W, and Ta contents are of particular interest when investigating AlCrSi(W, Ta)N films as they enable both grain-refining as well as solid solution hardening mechanisms, thus positively influencing the hardness, wear, and oxidation resistance.The overall objective of this research project is to holistically combine the results of the analyses of the interactions between the chemical compositions and phase compositions of new target materials with the resulting tribo-mechanic coating properties of nanocomposite structures. Especially, the influence of the W and Ta contents on the oxidation behavior is closely scrutinized. Finally, the examined AlCrSi(W, Ta)N coating systems will be applied on cutting tools to analyze the influence of the doping elements and to verify these influences under real production conditions.