31. In the 1930s, this research was supplemented with works on the theory of plastic deformation . 32. Mechanisms of crystal-plastic deformation include Pressure solution, Dislocation creep, and Diffusion creep. 33. Stronger materials must undergo either elastic deformation or plastic deformation to absorb an impact without breaking. 34. This micro crack can initiate permanent plastic deformation which results in large crack propagation or failure. 35. Under tensile stress, plastic deformation is characterized by a strain hardening region and a atomic dislocations. 36. Eventually the stress is great enough to overcome the strain-field interactions and plastic deformation resumes. 37. A material's toughness is a factor of its ability to absorb energy during plastic deformation . 38. I'd say start over, write a proper plastic deformation , incrementally, with references. 39. Plastic deformation is when a material deforms but does not return to it's original shape.40. Under excessive tensile strain, the tubes will undergo plastic deformation , which means the deformation is permanent.
