UAIPD 09-0027

09-0027 “Low stressed functional diamond

film”Inventor: Dr. Kevin Chou

• Drills are critical to productivity and part quality in the manufacturing process.–Most widely used are cobalt-cemented

tungsten (Co-WC) carbide twist drills• Diamond coatings are used to extend tool

life due to high hardness and low friction. – BUT these coatings suffer from adhesion

problems, residual stresses, and have a thickness threshold.

Current Problems

• Method of drill design that lowers the stress of diamond coating on twist drill.– Achieved by perfecting

the geometry of drill design on both the macro and micro level.

• Decreases delamination of coating by reducing the amount of stress.

Technology

• Easy fabrication that utilizes geometry modification to reduce stress.

• Proven advantages through rigorous engineering analysis

Advantages

Drill life,# of holes Comment40 Drill breakage

>100No drill breakage, testing stop for drill evaluation

Engineered edge

Original edge

• Dr. Kevin Chou– Professor– 27 Publications

• Departments– Center for Advanced Vehicle Technologies–Mechanical Engineering

Inventor

kchou@eng.ua.edu

Office for Technology Transfer720 2nd Ct E

Tuscaloosa, AL 35401UAIPD09-0027OTT@UA.edu

www.OTT.UA.edu