Markovsky Pavlo E, Janiszewski Jacek, Stasyuk Oleksandr O, Bondarchuk Vadim I, Savvakin Dmytro G, Cieplak Kamil, Goran Daniel, Soni Purvesh, Prikhodko Sergey V
G.V. Kurdyumov Institute for Metal Physics of N.A.S. of Ukraine, 03412 Kyiv, Ukraine.
Jarosław Dąbrowski Military University of Technology, 00908 Warsaw, Poland.
Materials (Basel). 2021 Nov 12;14(22):6837. doi: 10.3390/ma14226837.
The mechanical behavior of titanium alloys has been mostly studied in quasi-static conditions when the strain rate does not exceed 10 s, while the studies performed in dynamic settings specifically for Ti-based composites are limited. Such data are critical to prevent the "strength margin" approach, which is used to assure the part performance under dynamic conditions in the absence of relevant data. The purpose of this study was to obtain data on the mechanical behavior of Ti-based composites under dynamic condition. The Metal Matrix Composites (MMC) on the base of the alloy Ti-6Al-4V (wt.%) were made using Blended Elemental Powder Metallurgy with different amounts of reinforcing particles: 5, 10, and 20% of TiC or 5, 10% (vol.) of TiB. Composites were studied at high strain rate compression ~1-3 × 10·s using the split Hopkinson pressure bar. Mechanical behavior was analyzed considering strain rate, phase composition, microstructure, and strain energy (SE). It is shown that for the strain rates up to 1920 s, the strength and SE of MMC with 5% TiC are substantially higher compared to particles free alloy. The particles TiC localize the plastic deformation at the micro level, and fracturing occurs mainly by crushing particles and their aggregates. TiB MMCs have a finer grain structure and different mechanical behavior. MMC with 5 and 10% TiB do not break down at strain rates up to almost 3000 s; and 10% MMC surpasses other materials in the SE at strain rates exceeding 2200 s. The deformation mechanism of MMCs was evaluated.
钛合金的力学行为大多是在应变速率不超过10 s的准静态条件下进行研究的，而专门针对钛基复合材料在动态环境下进行的研究则较为有限。这些数据对于防止在缺乏相关数据时用于确保零件在动态条件下性能的“强度裕度”方法至关重要。本研究的目的是获取钛基复合材料在动态条件下的力学行为数据。采用混合元素粉末冶金法制备了以Ti-6Al-4V（重量百分比）合金为基体、含有不同数量增强颗粒的金属基复合材料（MMC）：5%、10%和20%的TiC或5%、10%（体积）的TiB。使用分离式霍普金森压杆对复合材料在~1-3×10·s的高应变速率压缩下进行了研究。从应变速率、相组成、微观结构和应变能（SE）方面对力学行为进行了分析。结果表明，对于应变速率高达1920 s的情况，含有5% TiC的MMC的强度和SE与无颗粒合金相比显著更高。TiC颗粒在微观层面使塑性变形局部化，断裂主要通过颗粒及其聚集体的破碎发生。TiB基MMC具有更细的晶粒结构和不同的力学行为。含有5%和10% TiB的MMC在应变速率高达近3000 s时不会破裂；在应变速率超过2200 s时，10%的MMC在SE方面超过其他材料。对MMC的变形机制进行了评估。
