Intrinsic normal stress differences

K, as well as for mean normal stresses of 4.14, 6.3, and 12.4 MPa at 253 K at different levels of simultaneously applied deviatoric stress s. In all cases craze initiation was considered complete at 10 s, when around 10 crazes per cm had formed. Table 11.1 gives the specific three pairs of a and s for 293 K and 253 K for craze initiation, together with dimensionless representations of stresses by parameters and tj, for and s normalized with appropriate uniaxial compressive yield stresses Tq = 103 MPa at 293 K and 144 MPa at 253 K, respectively. The three combinations of stress parameters and tj for crazing at 293 K and 253 K are given in Fig. 11.3, together with the information on intrinsic crazing in flawless specimens in uniaxial tension. 

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