文章信息/Info

Title:

Research on the Mechanical Behavior and Deformation Failure Mechanism of SiC/AZ91D Composites with Particles Mixing Based on Actual Three Dimensional Microstructure

文章編號(hào):

1674-3962(2025)08-0770-08

作者:

陳國(guó)鑫 堯軍平 梁超群 李步煒 李怡然

南昌航空大學(xué)航空制造工程學(xué)院，江西 南昌 330000

Author(s):

CHEN Guoxin;  YAO Junping;  LIANG Chaoqun;  LI Buwei;  LI Yiran

School of Aeronautical Manufacturing Engineering, Nanchang Hangkong University, Nanchang 330000, China

關(guān)鍵詞:

顆粒混雜; SiC/AZ91D復(fù)合材料; 有限元模型; 單軸壓縮; 裂紋萌生

Keywords:

particles mixing;  SiC/AZ91D composites;  finite element model;  uniaxial compression;  crack initiation

分類號(hào):

TB333

DOI:

10.7502/j.issn.1674-3962.202310016

文獻(xiàn)標(biāo)志碼:

A

摘要:

基于復(fù)合材料真實(shí)微觀結(jié)構(gòu)，在顆粒與基體界面引入內(nèi)聚力單元，建立了3種不同顆粒混雜比增強(qiáng)的復(fù)合材料的有限元模型，模擬研究了SiC顆�；祀s的SiC/AZ91D復(fù)合材料單軸壓縮時(shí)的力學(xué)行為及其變形失效機(jī)理。結(jié)果表明：等效粒徑為5和10 μm的顆粒混雜增強(qiáng)的復(fù)合材料較單粒徑顆粒增強(qiáng)的復(fù)合材料具有更高的屈服強(qiáng)度和抗壓強(qiáng)度，壓縮率介于兩種單粒徑顆粒增強(qiáng)的復(fù)合材料之間，顆�；祀s可以延緩復(fù)合材料裂紋萌生和裂紋擴(kuò)展過(guò)程。隨著5和10 μm的顆粒的體積混雜比增大，復(fù)合材料的屈服強(qiáng)度、抗壓強(qiáng)度和壓縮率也隨之增加，顆�；祀s比越大，越有利于抑制裂紋萌生擴(kuò)展，裂紋長(zhǎng)度越長(zhǎng)。顆�；祀s增強(qiáng)的復(fù)合材料裂紋萌生擴(kuò)展機(jī)制是：顆粒群尖角處應(yīng)力集中程度較高，導(dǎo)致基體受損形成微裂紋，這些微裂紋沿著最大切應(yīng)力方向擴(kuò)展，匯聚成主裂紋導(dǎo)致材料斷裂。

Abstract:

Based on the real microstructure of the mixed particles�瞨einforced composites, the cohesive unit was introduced at the interface between the particles and the matrix, three finite element models with different particles mixing ratios were established, the mechanical behavior during uniaxial compression and deformation failure mechanism of the SiC/AZ91D composites were studied. The results show that the yield strength and compressive strength of the mixed particles-reinforced composites with equivalent particle sizes of 5 μm and 10 μm are greater than those of the single-particle reinforced composites, and the compression ratio is in the range of those of the two single-particle reinforced composites, particles mixing can delay the initiation and propagation of cracks in composite materials. The larger the 5 μm particle and 10 μm particle mixing volume ratio, the higher the yield strength, compressive strength and compression ratio of the composite; with the particle mixing volume ratio increasing, the initiation and propagation of cracks are more suppressed, the final crack length is longer. The mechanism of crack initiation and propagation of the composite materials is due to the serious stress concentration at the boundary and sharp corner of SiC particles group,resulting in matrix damage and microcrack initiation, and microcracks propagate and converge into main crack along the maximum shear stress direction.