We observed residual stress relaxation by CO(2) laser irradiation in the cores of optical fibers by direct stress measurement. It was demonstrated that the mechanical stress was fully relaxed by CO(2) laser irradiation and that the remaining stress in the core was thermal stress that was due to a mismatch of the thermal expansion coefficients of the fiber core and cladding. The net core stresse...

In this study, Thermal expansion coefficient (TEC) variation of Ln0.6Sr0.4Co0.2M0.8O3−δ (Ln=La,Nd,Sm and M= Fe,Ni,Mn) perovskite oxide have been evalouated. Different compounds have been prepared and thermal expansion coefficient have been meseaured in different temperature by means of dilatometer analysis. Structural parameters of compounds have been  determined by X-ray diffraction and Field ...

The use of strain gages for low temperature thermal expansion measurements is increasing, due to it's convenience, and relative accuracy. The determination of thermal expansion with strain gages is complicated by "thermal output strain", a phenomena caused by the temperature dependence of the gage. If thermal output strain is properly compensated , strain gages may be used to measure thermal ex...

Size effects on Volume thermal expansion of nanomaterials. The experimental measurements show that volume thermal expansion of nanosolids is larger than those of their bulk counterparts. On considering the surface effect, a simple model is derived to study the size dependence of volume thermal expansion of nanomaterials for spherical nanoparticles, nanowire and nanofilms. The size dependence of...