In this paper, an experimental investigation is performed using acoustic emission (AE) technique to study the behaviour of crack initiation and propagation of woven carbon fibre reinforced plastic (CFRP) composites un...In this paper, an experimental investigation is performed using acoustic emission (AE) technique to study the behaviour of crack initiation and propagation of woven carbon fibre reinforced plastic (CFRP) composites under static tensile loading. Three laminates with three plies each were manufactured and tested under tensile static loading. Damage was being monitored using AE technique with instantaneous AE hits energies being used as the damage parameter. Results showed that angle ply laminates experienced crack initiations at about 50% of ultimate tensile strength whereas cross ply laminates and non-conventional angle ply laminates having one cross ply laminate experienced initiation of cracks at about a third of ultimate tensile strength. This early cracks initiation is believed to be caused by the presence of 90° plies that cannot take much load transversely.展开更多
Using module class C R=Mx∈M,xRT=0,T∈I , we introduced the concepts of C R finitely generated module, C R finitely presented module and C R regular ring. We also discussed the criterion for C ...Using module class C R=Mx∈M,xRT=0,T∈I , we introduced the concepts of C R finitely generated module, C R finitely presented module and C R regular ring. We also discussed the criterion for C R regular ring,and the relations between C R regular ring and C R FP injective module.展开更多
文摘In this paper, an experimental investigation is performed using acoustic emission (AE) technique to study the behaviour of crack initiation and propagation of woven carbon fibre reinforced plastic (CFRP) composites under static tensile loading. Three laminates with three plies each were manufactured and tested under tensile static loading. Damage was being monitored using AE technique with instantaneous AE hits energies being used as the damage parameter. Results showed that angle ply laminates experienced crack initiations at about 50% of ultimate tensile strength whereas cross ply laminates and non-conventional angle ply laminates having one cross ply laminate experienced initiation of cracks at about a third of ultimate tensile strength. This early cracks initiation is believed to be caused by the presence of 90° plies that cannot take much load transversely.
文摘Using module class C R=Mx∈M,xRT=0,T∈I , we introduced the concepts of C R finitely generated module, C R finitely presented module and C R regular ring. We also discussed the criterion for C R regular ring,and the relations between C R regular ring and C R FP injective module.