TY - JOUR
T1 - Investigation of Internal Cracks in Epoxy-Alumina Using In Situ Mechanical Testing Coupled with Micro-CT
AU - Tang, Yichun
AU - Su, Kangning
AU - Man, Ruyi
AU - Hillman, Michael C.
AU - Du, Jing
N1 - Publisher Copyright:
© 2021, The Minerals, Metals & Materials Society.
PY - 2021/8
Y1 - 2021/8
N2 - Polymer-ceramic composites are widely used in biomedical applications. This paper presents the results of an experimental investigation on the crack extension inside epoxy-alumina. Specimens with 5 vol.%, 10 vol.%, …, 25 vol.% fillers fractions were fabricated. Three-point bending on single-edge notched bend specimens were performed using conventional mechanical tester and in situ mechanical tester coupled with micro-CT, respectively. Fracture toughness was measured to be 2.10–2.51 MPam, and it decreased with increasing filler fraction. When cracks were shorter than 0.88 mm, crack resistance for 5 and 25 vol.% epoxy-alumina was similar. Beyond 0.88 mm, 25 vol.% epoxy-alumina exhibited no crack resistance, whereas stress intensity factor kept increasing in 5 vol.% epoxy-alumina. The matrix-particle interfaces were the weakest link, where cracks often initiated from. Crack bridging by uncracked ligament and crack deflection were commonly observed toughening mechanisms. To design robust epoxy-alumina composites, increasing matrix-particle interface strength is recommended for future work.
AB - Polymer-ceramic composites are widely used in biomedical applications. This paper presents the results of an experimental investigation on the crack extension inside epoxy-alumina. Specimens with 5 vol.%, 10 vol.%, …, 25 vol.% fillers fractions were fabricated. Three-point bending on single-edge notched bend specimens were performed using conventional mechanical tester and in situ mechanical tester coupled with micro-CT, respectively. Fracture toughness was measured to be 2.10–2.51 MPam, and it decreased with increasing filler fraction. When cracks were shorter than 0.88 mm, crack resistance for 5 and 25 vol.% epoxy-alumina was similar. Beyond 0.88 mm, 25 vol.% epoxy-alumina exhibited no crack resistance, whereas stress intensity factor kept increasing in 5 vol.% epoxy-alumina. The matrix-particle interfaces were the weakest link, where cracks often initiated from. Crack bridging by uncracked ligament and crack deflection were commonly observed toughening mechanisms. To design robust epoxy-alumina composites, increasing matrix-particle interface strength is recommended for future work.
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U2 - 10.1007/s11837-021-04714-x
DO - 10.1007/s11837-021-04714-x
M3 - Article
AN - SCOPUS:85105805194
SN - 1047-4838
VL - 73
SP - 2452
EP - 2459
JO - JOM
JF - JOM
IS - 8
ER -