The Local Knowlege

Gear & Equipment

The story behind the boron steel in Mizuno's JPX850 Forged irons

By Mike Stachura

Luxury cars use high-strength boron-steel reinforcement beams to improve collision resistance. How tough are these boron steels? Here's a writeup from a journal that provides technical advice for fire departments and EMS rescue teams charged with extricating injured drivers from car crashes: 

"Without a practically brand new hydraulic power cutter, the rescuer might find that they will be unable to cut through any of the areas where the advanced steel is located. Unless your power cutter is new, or within one or two years old, you might not be able to cut the roof off for example or even lay a B-pillar down after a T-bone collision. Older generation power cutters most likely won’t be able to cut this stuff! Your air chisel bits will all break before the boron steel will even make a dent. The teeth on your best demolition quality reciprocating saw blade will quickly be worn off without so much as even scratching the advanced steel.”

Now Mizuno is using a version of these new high-strength steels to make its forged irons produce faster ball speeds.

loop-mizuno-jpx850-iron-518.jpgThe new JPX850 Forged irons ($1,000) feature a boron-infused 1025 carbon steel for a thinner face with a higher springlike effect than any other Mizuno one-piece forged iron. The metal's strength also allows designers to mill a pocket cavity that comes within 1.7 millimeters of the face and 1.5 millimeters of the sole to increase face flexibility.

The combination of the unique material and design saves 26 grams that is redistributed around the perimeter for enhanced stability.

Interested in more stories on equipment? Signup to receive Golf Digestix, a weekly digital magazine that offers the latest news, new product introductions and behind-the-scenes looks at all things equipment.