Effects of porosity on in-plane and interlaminar shear strengths of two-dimensional carbon fiber reinforced silicon carbide composites. (15th May 2016)

• Record Type: Journal Article
• Authors: Zhang, Yi; Zhang, Litong; Yin, Xiaowei; Liu, Yongsheng; He, Zongbei; Zhang, Jiaxin
• Is Part Of: Materials & design. Volume 98(2016)
• Page Start: 120
• Page End: 127
• Publication Date: 2016-05-15
• Subjects: Ceramic matrix composites (CMCs) -- Cracking -- Porosity -- Shear; Materials -- Periodicals; Engineering design -- Periodicals; Matériaux -- Périodiques; Conception technique -- Périodiques; Electronic journals; 620.11
• DOI: 10.1016/j.matdes.2016.03.017
• Languages: English
• ISSNs: 0264-1275

Abstract

Abstract: Porosity effects on shear properties of 2D C/SiC were investigated based on the corresponding shear damage mechanisms. The results show that as the total porosity increases from 12.2% to 26.1%, the interlaminar shear strength decreases from 44.58 MPa to 17.80 MPa according to a power law, while the in-plane shear strength decreases linearly from 143.25 MPa to 74.38 MPa. Under interlaminar shear stress, delamination is resulted from matrix cracking and interface debonding/sliding mechanisms. Effects of porosity on interlaminar shear strength is controlled by the volume fraction of the delaminated matrix. Under in-plane shear stress, echelon matrix shear cracking and large scale fiber bridging mechanisms occur. The decreasing of in-plane shear strength depends on the spacing between the echelon cracks. Since the interface debonding/sliding mechanism occurs under both in-plane and interlaminar shear stresses, a relationship is obtained that the in-plane shear strength equals the sum of the interlaminar shear strength and the fiber bridging term under the minimum total porosity about 30.5%. Graphical abstract: Highlights: Interlaminar shear strength decreases with the increase of porosity according to a power law. In-plane shear strength decreases linearly with the increase of porosity. The decreasing of interlaminar shear strength is controlled by the volume fraction of the delaminated matrix. The decreasing of in-plane shear strength depends on the spacing between echelon matrix shear cracks.