Composite baseball bat

Bats which only incorporate a portion of polymer (and the rest either wood or an aluminum alloy) are referred to as composite hybrids.

[1] As a result, a new standard, known as the batted-ball coefficient of restitution (BBCOR), was put in place in 2011 which required an accelerated break in period and testing to measure the trampoline effect of composite bats.

[2] Since the new restrictions on composite baseball bats NCAA hitting production has been noticeably dampened.

[4] Even though composite material has only been historically used in slow-pitch and softball, this technology has emerged in little league, high school and collegiate baseball as early as 2000.

MLB or affiliates for short season and rookie ball does allow a select few composite wood bats.

Specifically, the rebound rate or trampoline effect, after an accelerated break in period, must stay under certain requirements.

[6] Other bat dimensions are akin to wood and aluminum alloy requirements (length, barrel diameter, etc.).

In December 2010, Little League Baseball announced a moratorium on the use of composite bats due to concerns about safety of young players.

This softer barrel allows the ball to come off with less energy loss while maintaining the stiffness of the bat in the handle.

Daniel A. Russell of Kettering University has shown that standard aluminum bats have a high bending stiffness that produces vibrational frequencies in the range where most hands are sensitive; therefore, causing more sting.

[4] Including the lower bending stiffness, composite baseball bats have a higher damping rate.

On July 22, 2009, the NCAA reported that the rules committee had requested to ban the use of composite bats.

The NCAA Playing Rules Oversight Panel found that 20 out of the 25 composite bats tested during the 2009 NCAA Division 1 Baseball Tournament failed the BESR (Ball Exit Speed Ratio) test.

During this temporary ban, the rules committee will continue testing the bats to determine if the performance is enhanced through repetitive use, or if intentional alteration seems more plausible.

USA Baseball has repeatedly stated that the USA Bat Standard is for the betterment of the sport because it will uphold the “long term integrity of the game” with injuries and financial profits not playing a role in the decision.

[14] Some leagues and tournament continue to allow the older USSSA 1.15 BPF bats which have considerably higher trampoline effect and are more similar to the old OWEN bats no longer allowed in high school and NCAA.