Please contact me ASAP regarding 22 mm chrome plated, piston rod for automtive application, front struts. Volume = 40k vehicles per year, 80k struts/year. Looking for an increase in yield strength over current rod that's 22 mm, 1.3 mm case depth, external hardness of 550 Hv. Is there a chance to achieve a higher yield strength w/ a hollow rod that has a case depth of 3 to 4 mm?