Quasi-static fracture toughness

Quasi-static fracture toughness values, Kc were calculated according to equation (1) ... 

Fig. 9 Loading rate dependence of quasi-static fracture toughness values, determined by an FBA method and dynamic fracture toughness values, Kj, determined by the DKC method for Charpy type fracture specimens of (a) PC and (b) POM.

VI.24] INTERNATIONAL ORGANIZATION FOR STANDARDIZATION, ISO/TC164/SC4 — Discussions on a Unified Method of Test for Quasi-static Fracture Toughness — N128, ISO, Geneva (1994). 

Table 3.1 Room temperature dynamic and quasi-static fracture initiation toughness values of the ceramic materials tested in the present study...

Jic is the critical value of the near-tip quasi-static fracture parameter J, i.e. the crack initiation toughness. As for ductile materials a stable crack growth can occur at J values several times the value J c, the non-dimensional tearing modulus Tr was proposed for defining the crack growth toughness [26] ... 

The main results of this miero-mechanical model in the quasi-static regime have been compared with experimental results obtained by placing polystyrene (PS)-polyvinyl pyridine (PVP) diblock copolymers with a short PVP block between PS and PVP homopolymers. The fracture toughness was found to increase linearly with E from that of the bare PS/PVP interface, while the slope of the line increased with the degree of polymerization of the block being pulled out. If the data for the different copolymers were plotted as AG vs. (where... 

A summary of quasi-static delamination test methods for continuous-fibre, unidirectional FRP composites is given in Table 8.1. For mode 1, several standard test methods exist, namely, JIS K7086 ( Testing methods for interlaminar fracture toughness of carbon fibre reinforced plastics , 1993) this also includes a quasi-static mode 11 standard test, ASTM... 

The literature published on fracture mechanics testing of FRPs in the last 40 years comprises a large database on delamination resistance or fracture toughness of different types of FRPs. An early review [51] compiled the data available at that time. Selected data from quasi-static mode I and mode II tests on FRPs were compared by O Brien [52], and quasi-static mode I test data from carbon—fibre epoxy and poly-ether-ether-ketone (PEEK) by Brunner [53]. Mechanical properties of FRP composites are compiled in the Composite Materials Handbook version F (2002) [9—11], but this does not comprise fracture mechanics data. Hence, there is no comprehensive and up-to-date database on the available data or literature. 

Cure pressure for woven CFRP epoxy was varied in three steps (0.69, 0.31 and 0.10 MPa) by Li and Crosky [72] and affected physical and mechanical properties, including the interlaminar fracture toughness of the laminates. A comparison of different processes (autoclave versus proprietary Quickstep ) for a unidirectional CFRP epoxy (T800H/3900-2) indicated similar quasi-static mode I values (554 and 527 J/m, respectively) but a significantly increased fatigue performance for the latter [73]. 

Fig. 2.6 Crack propagation rate as a function of cyclical component of the stress intensity factor at fatigue conditions for thermoplastic polymers, A o - onset value of crack propagation, - fracture toughness at quasi-static loading conditions C and m - material parameters.

Quasi-Static Loading of Thermoplastics - Data Polymer Solids and Polymer Melts R. Lack, W. Grellmann Quasi-Static Loading Table 5.1 Fracture toughness of thermoplastics at quasi-static loading (RT - room temperature 20 -25 °C). ... 

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