泡沫FeSiB/316L复合材料制备及压缩吸能特性

Preparation and compression energy absorption properties of foam FeSiB/316L composites

关键词:  泡沫FeSiB/316L复合材料  粉末冶金  造孔剂  压缩强度  吸能

Key words:  foam FeSiB/316L composites  powder metallurgy  pore-forming agent  compressive strength  energy absorption

摘要:

为了制备高强度、轻质泡沫钢材料,并提高其在吸能方面的性能。本文以FeSiB为第二相增强相,以316L不锈钢粉与不同质量分数(0%、5%、10%、15%)FeSiB粉的混合粉末作为原料、无水CaCl₂颗粒为造孔剂,采用粉末冶金烧结-溶解法制备泡沫FeSiB/316L复合材料。利用扫描电镜(SEM)和X射线衍射(XRD)对试样进行微观组织结构分析,并对试样进行轴向准静态压缩测试,分析讨论了不同质量分数的FeSiB对泡沫钢压缩变形行为和吸能特性的影响。研究表明:泡沫FeSiB/316L复合材料孔结构多为不规则形状且分布均匀；当FeSiB添加量在0%～15%时,随着FeSiB含量的增加,复合材料的压缩强度从42.61 MPa开始逐步提高,最高达到100.26 MPa；阐明了材料力学性能的增强机理,主要归因于晶粒细化和第二相析出强化的叠加效应,且第二相析出强化起决定性作用；随着FeSiB含量的增加,复合材料的能量吸收值逐步增大,当应变量为10%～40%时,孔隙率为63.32%的15%泡沫FeSiB/316L复合材料,其单位体积的能量吸收值约为泡沫铝的7～8倍,这表明其具有更加优良的吸能特性；随着FeSiB含量的增加,复合材料的理想吸能效率逐步提高,最高可达0.77,表明泡沫FeSiB/316L复合材料相较于纯316L泡沫钢更接近于理想的吸能材料。

Abstract:

In order to prepare high-strength and light-weight foam steel material and improve its performance in energy absorption, the foam FeSiB/316L composites were prepared by powder metallurgy sintering-dissolution method, using 316L stainless steel powder and FeSiB powder with different mass fractions (0%、 5%、 10%、 15%) as raw materials and anhydrous CaCl₂ particles as pore-forming agent. The microstructure of the samples was analyzed by SEM and XRD, and the quasi-static compression test was carried out on the samples The effects of different mass fractions of FeSiB on the compressive deformation behavior and energy absorption characteristics of foam steel were analyzed and discussed. The results show that the pore structure of foam FeSiB/316L composites is mostly irregular and evenly distributed. When the mass fraction of FeSiB is 0%-15%, with the increase of FeSiB content, the compressive strength of foam FeSiB/316L composite is up to 100.26 MPa. When the strain is 10%-40%, the energy absorption value per unit volume of 15% foam FeSiB/316L composite is about 7-8 times that of aluminum foam. The ideal energy absorption efficiency (I) of the FeSiB/316L foam composite can reach up to 0.77, which indicates that the FeSiB/316L foam composite is closer to the ideal energy absorption material than the pure 316L foam steel.