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A simple theory of latent hardening in crystals, recently proposed by the authors [1], is applied to the determination of anisotropic hardening in slip systems of face-centered cubic crystals in the tensile test, based upon a parabolic resolved-shear-stress versus slip curve in the active system. The theory predicts the generally observed continuation of finite single slip beyond the crystallographic symmetry line. Moreover, the predicted diversity of finite distortional hardening among latent slip systems is in qualitative agreement with experiment.

Articles you may be interested inSurface relaxation effect on the distributions of energy and bulk stresses in the vicinity of Cu surface: An embedded-atom method study J. Appl. Phys.The Bridgman analysis gives the stress distribution at the minimum cross section h neck in a round tensile specimen. Consequently, the Bridgman analysis is essentially one dimensional since only radial variation (at constant axial position) is considered. In the present analysis the assumptions made by Bridgman are assumed valid for other cross sections close to the neck. A method suggested by Kaplan is then used to extend the Bridgman analysis to obtain the stresses as a function of both radial and axial position.

Background:The introduction of adhesive dentistry has spurred research into finding solutions for the facilitation of daily dental adhesive workflow to achieve a durable and reliable adhesive junction using newly introduced instruments & techniques in the dental field. Aim of the study: to evaluate the SBS to enamel surfaces treated using conventional acid etching compared to Er,Cr:YSGG laser at two average power outputs as well as in combination with each other.Materials and Methods: 50 human molars were used. The molars were embedded in acrylic blocks with their buccal surfaces facing upwards. Enamel was removed using an Isomet 4000 exposing superficial dentin and a surrounding enamel rim. The specimens were divided into five equal groups with ten samples in each group GI:Acid Etching, GII:3.5 watt Er,Cr:YSGG Laser, GIII:3.5 watt Er,Cr:YSGG + AE Laser, GIV:4.5 watt Er,Cr:YSGG Laser and GV:4.5 watt Er,Cr: YSGG Laser + AE. Universal microhybrid composite microcylinders were then bonded to the enamel rim using Tygon tubes which were then subjected to microshear bond testing using a universal testing machine and the SBS were recorded and tabulated. One-way ANOVA followed by Duncan's Post-hoc tests were used to compare between the different groups. Results: The SBS values showed that values of GIV were similar to those obtained from GII and showed no statistical significance. Both groups, however, showed higher significant values than the remaining groups. Conclusion:Low average power output Er,Cr: YSGG laser has a beneficial effect in enhancing the bonding of etch and rinse adhesives to enamel.