Week One

Introduction 

Contributors:

Erika Rugh – Undergraduate senior at Sweet Briar College majoring in engineering

Collin Malek – Undergraduate senior at Oakland University majoring in mechanical engineering

Project Description:

This project aims to better implement high and ultra-high strength steels in the automotive industry which allows for an improved fuel economy. Specifically, this program addresses the problem of splitting from the sheared edge that occurs when tension is applied along the sheared surface.  Presented by Dr. Golovashchenko, the following are the goals of this assignment.

1. Study sheared surface parameters (burr height, burnished area - indentation of the tool before initiation of fracture, height of the brittle zone and rollover zone) for the range of cutting clearances by: a) observing the sheared surface under the microscope and b) preparing crosssections for several steels employed in automotive industry, such as Interstitial Free steel, Bake Hardenable steel, High Strength Low Alloy Steel and Dual Phase Steel DP980.
2. Understand the effects of tool wear during trimming process on sheared edge parameters by: a) comparing the burnished areas of trimmed samples selected after specified number of cuts and b) performing stretchability experiments of these selected samples.
3. Analyze the mechanism of fracture of sheared samples as a function of cutting clearance and cutting edge condition and locate initiation of fracture during stretching of sheared edge of sheet metal samples.
4. Compare sheared edge stretchability for sheared surfaces fabricated by piercing 10mm in diameter holes and trimmed along the straight line by measuring the strains along the perimeter of stretched sheared edge.