An experimental study was carried out on the strain cyclic characteristics and ratcheting of 316L stainless steel subjected to uniaxial and multiaxial cyclic loading. The strain cyclic characteristics were researched ...An experimental study was carried out on the strain cyclic characteristics and ratcheting of 316L stainless steel subjected to uniaxial and multiaxial cyclic loading. The strain cyclic characteristics were researched under the strain-controlled uniaxial tension-compression and multiaxial circular paths of loading. The ratcheting tests were conducted for the stress-controlled uniaxial tension-compression and multiaxial circular, rhombic and linear paths of loading with different mean stresses, stress amplitudes and histories. The experiment results show that 316L stainless steel features the cyclic hardening, and its strain cyclic characteristics depend on the strain amplitude and its history apparently. The ratcheting of 316L stainless steel depends greatly on the Values of mean stress, stress amplitude and their histories. In the meantime, the shape of load path and its history also apparently influence the ratcheting.展开更多
The uniaxial ratcheting behavior of a polyetherimide (PEI) polymer 'TECAPEI' was studied using stress-controlled cyclic loading at room temperature, including both cyclic tension-compression with non-zero tens...The uniaxial ratcheting behavior of a polyetherimide (PEI) polymer 'TECAPEI' was studied using stress-controlled cyclic loading at room temperature, including both cyclic tension-compression with non-zero tensile mean stress and tension- unloading tests. The experimental observations were focused on the time-dependent ratcheting of the PEI polymer revealed in cyclic tests at diverse stress rates and with different peak stress holding times. The results showed that the PEI polymer shows obvious ratcheting deformation; i.e., the ratcheting strain accumulates progressively in the tensile direction during stress- controlled cyclic tests with non-zero mean stress. The ratcheting is highly dependent on the applied mean stress and stress am-plitude, and is also characterized by a strong time-dependency during the cyclic stressing at diverse stress rates and with different peak stress holding times. The time-dependent ratcheting of the PEI polymer is caused mainly by its remarkable viscosity. A comparison of the ratcheting occurring before and beyond the ultimate stress point of the PEI polymer showed that the ratcheting beyond the ultimate stress point is more significant than that occurring before that point.展开更多
文摘An experimental study was carried out on the strain cyclic characteristics and ratcheting of 316L stainless steel subjected to uniaxial and multiaxial cyclic loading. The strain cyclic characteristics were researched under the strain-controlled uniaxial tension-compression and multiaxial circular paths of loading. The ratcheting tests were conducted for the stress-controlled uniaxial tension-compression and multiaxial circular, rhombic and linear paths of loading with different mean stresses, stress amplitudes and histories. The experiment results show that 316L stainless steel features the cyclic hardening, and its strain cyclic characteristics depend on the strain amplitude and its history apparently. The ratcheting of 316L stainless steel depends greatly on the Values of mean stress, stress amplitude and their histories. In the meantime, the shape of load path and its history also apparently influence the ratcheting.
基金Project (No 2008TPL_Z03) supported by the Key Open Foundation of State Key Laboratory of Traction Power, China
文摘The uniaxial ratcheting behavior of a polyetherimide (PEI) polymer 'TECAPEI' was studied using stress-controlled cyclic loading at room temperature, including both cyclic tension-compression with non-zero tensile mean stress and tension- unloading tests. The experimental observations were focused on the time-dependent ratcheting of the PEI polymer revealed in cyclic tests at diverse stress rates and with different peak stress holding times. The results showed that the PEI polymer shows obvious ratcheting deformation; i.e., the ratcheting strain accumulates progressively in the tensile direction during stress- controlled cyclic tests with non-zero mean stress. The ratcheting is highly dependent on the applied mean stress and stress am-plitude, and is also characterized by a strong time-dependency during the cyclic stressing at diverse stress rates and with different peak stress holding times. The time-dependent ratcheting of the PEI polymer is caused mainly by its remarkable viscosity. A comparison of the ratcheting occurring before and beyond the ultimate stress point of the PEI polymer showed that the ratcheting beyond the ultimate stress point is more significant than that occurring before that point.
