Can you explain how the process of quenching influences the mechanical properties of materials, and its effects on the stress-strain curve?

Start by explaining the quenching process in materials science - it involves the rapid cooling of a material to adjust its crystal structure and thereby enhance its mechanical properties. Discuss how this process can modify the material's hardness, toughness, and ductility, among other properties, and how these changes are reflected on the stress-strain curve of the material. You might also delve into the potential downsides of quenching, such as the introduction of residual stresses or increased brittleness, and how engineers can mitigate these effects through processes like tempering. Relate the discussion back to the specific changes you would observe in the stress-strain curve, such as shifts in the yield point or changes in the material's ultimate tensile strength. To give a complete picture, you might consider discussing an example of a material commonly quenched and how quenching influences its application in industry.