Graded microstructure and mechanical properties of additive manufactured Ti–6Al–4V via electron beam melting

Advanced Issues in springback

Prediction of shear-induced fracture in sheet metal forming

Welding and Joining of NiTi Shape Memory Alloys: A Review

https://www.tpbin.com/Uploads/Subjects/0611b255-45d7-457a-8988-9c77b24b09c0.pdf

Complex unloading behavior: Nature of the deformation and its consistent constitutive representation

As the springback of sheet metal during unloading may cause deviation from a desired shape, accurately predicting springback is essential for the design of sheet stamping operations Finite-element

Analytical prediction of springback based on residual differential strain during sheet metal bending

Failure during sheared edge stretching of sheet steels is a serious concern, especially in advanced high-strength steel (AHSS) grades. The shearing process produces a shear face and a zone of deformation behind the shear face, which is the shear-affected zone (SAZ). A failure during sheared edge stretching depends on prior deformation in the sheet, the shearing process, and the subsequent strain path in the SAZ during stretching. Data from laboratory hole expansion tests and hole extrusion tests for multiple lots of fourteen grades of steel were analyzed. The forming limit curve (FLC), regression equations, measurement uncertainty calculations, and difference calculations were used in the analyses. From these analyses, an assessment of the primary factors that contribute to the fracture during sheared edge stretching was made. It was found that the forming limit strain with consideration of strain path in the SAZ is a major factor that contributes to the failure of a sheared edge during stretching. Although metallurgical factors are important, they appear to play a somewhat lesser role.

Failure During Sheared Edge Stretching

Finite element analysis and experimental confirmation of warm hydroforming process for aluminum alloy

The Bauschinger behavior after a strain reversal was evaluated for samples with microstructures representative of production sheets for a low-carbon (LC) steel, a high-strength low-alloy (HSLA) steel, and a dual-phase (DP) steel. The microstructures were produced in the samples by laboratory hot rolling and heat treatment. Bauschinger tests were run at strain rates of 0.0001, 0.001, and 0.01 s−1, with tensile prestrains between 1 and 7 pct. After the reversal, the samples were strained 2 pct in compression. The Bauschinger effect is described by a Bauschinger effect parameter (BE), which is the difference between the steel strength at reversal and the 0.05 pct offset yield strength on the reversal, normalized by the steel strength at reversal. It is found that the Bauschinger effect is a continuous increasing function of the strength of the steel, provided the steel is prestrained at least 2.5 pct or beyond the yield point elongation. A single trend line describes the Bauschinger effect variation with steel strength, for all three steels in the present study and for an aluminum-killed drawing quality (AKDQ) steel from a previous investigation. No strain rate influence on the BE was found, due to the limited strain rate range and data uncertainty.

C.J. Van Tyne

Papers

Analytical prediction of springback based on residual differential strain during sheet metal bending

Failure During Sheared Edge Stretching

Finite element analysis and experimental confirmation of warm hydroforming process for aluminum alloy

Effect of strain and strain rate on the bauschinger effect response of three different steels

Application of a combined heating system for the warm hydroforming of lightweight alloy tubes