Stainless steel, Low Carbon Steel, 431, 304, 1020, 1025, 8620. There are more than enough materials to select from when it comes to making iron heads. While there isn’t really a “best” material to choose, many club-fitters do have a preference when it comes to selecting an iron they can work with depending on the type of player they are trying to fit. Here’s a quick comparison of the main types of steel popularly used in terms of bendability for different materials:
Low Carbon Steel (1020, 1025, and 8620)
Many irons these days are forged with a Low Carbon steel – either 1020 or 8620. Both are considered soft steels which bend easily. Thus making them great for a forged iron, and easy to manipulate in an iron fitting. Low Carbon steels can typically be bent up to 3 degrees.
304 Stainless Steel
304 Stainless Steel is the softest of the bunch. Some of our most popular irons like the Alpha C830.4 LX, Alpha Response iron (pictured above), and Silver Diamond T-Steel are all made from 304. These irons are lauded for the highest degree of bendability which is typically 5-7 degrees.
431 Stainless Steel
431 Stainless Steel is probably the most widely used type of steel in iron heads today mainly because it’s easily manufactured and produces consistent results. This steel is bendable only up to 2 degrees.
So you can see how the 304 Stainless Steel is exceptionally bendable in comparison to the rest of the materials. Bendability is almost always a necessary trait when doing an iron fitting.
Gary Winters, owner and club-fitter at Gairs Golf Shop and the Tee It Up Driving Range shares with us why: “I’ve done at least a thousand fittings. And I consistently find that 75% of the players fit to a lie angle outside of the normal range you’d find in a traditional iron spec. What this means is these players require the head to be more upright. It has to do with their angle of approaching the ball and what they are doing at impact. I fit them off a lie board and I always find it’s necessary to bend the lie angles.” Winters says he will normally need to bend lies anywhere from 3 to 8 degrees which helps the player tremendously in hitting accuracy and launch angle. “I only carry iron heads that I can alter and bend. And I primarily fit with heads that I can alter in the widest range, such as the Silver Diamond T-Steel and R5 heads.”
Winters says the softness of the 304 SS material gives players a feel similar to that of forged clubs, but without the hefty price tag. The only con he sees is that the softness of the iron may not work if you have a very fast swing speed, hit balls off of hard ground, or tend to take big divots. You might then alter the lie angle themselves just from the impact.
From a manufacturing standpoint, 304 Stainless Steel is actually more expensive to make iron heads with. Which is probably why it’s not as widely used by club manufacturers (most factories primarily make heads with 431). For us at Alpha Golf, our costs are actually 33% higher to make a 304 Stainless Steel iron head than with 431. However we believe in the necessity for a strong yet maleable head so club-fitters can make the proper adjustments needed for their players. One last trade-off of using 304 is that the face cannot be designed too thinly. The strength of the 304 is optimal with a medium face thickness. Therefore deep cavity back heads that require a thinner face for extra perimeter weighting will require a more rigid material such as 431.