Alligned Grain Flow with the JE Pistons’ Forging Technology

JE Pistons has successfully developed a new technology called Aligned Grain Flow Technology which is said to provide a breakthrough by offering additional strength without additional mass.

Aligned Grain Flow Technology is used exclusively in Je Pistons' new Ultra Series.

After several years of experimentation and development by JE Pistons’ Advanced Product Development group, AFT has been launched into the market in JE’s Ultra Series pistons.

  • For all JE Ultra Series Domestic Applications, CLICK HERE
  • For all JE Ultra Series Sport Compact Applications, CLICK HERE

This new technology is about making the best use of the grains of metal within the piston, as a cast piston is weaker than a forged one. The grains in the cast piston is larger and are more three dimensional in shape. The material for the forged piston is aluminium which is cut into piston sized slices so the grains have been worked into a longer and thinner form to attempt to prevent crack propagation. This further helps to optimise crack resistance where it really matter such as where the pin tower meets the crown.


“There were additional manufacturing steps that we had to take to ensure that the grain structure was in the proper locations,” says Cody Mayer, JE Piston’s Senior Manager of Advanced Product Development. “We further work those grains to stretch them and form them around the contours of the piston forging shape. Longer, thinner grains that are compressed more tightly together create additional grain boundaries in the most critical areas.”

“When a crack propagates through the material, it rarely happens all at once, especially in a fatigue situation in a reciprocating engine part that’s experiencing millions of load cycles,” says Mayer. “The crack starts very small and grows over thousands of cycles. But the elongated grains, packed tightly together, form walls to prevent the crack from progressing. The crack stops every time it hits a grain boundary. It’s much more difficult for it to propagate far enough through the piece to cause a failure.”


If the grain boundaries are placed at the most high stressed points, it is likely that fatigue cracks will be resisted more.

“We’ve focused on the crown of the piston, in particular where the pin tower meets the crown,” he continues. “We’ve wrapped grains around that joint and extended them across the face of the crown to resist the bending that combustion would normally induce. We’ve also applied them to the skirt.”

When creating connecting rods they also use a similar principle as the elongated shape allows for the grain advantages to be exploited. To begin with, JE Piston’s engineers used software to simulate the grain flow during the forging process. Subsequently, physical test samples were sectioned and etched to check the grain alignment after each change to the process.


An early step in the development of AFT was modelling the process digitally. That transitioned to testing on the actual forging press and laboratory analysis of forging samples.

JE’s forging facility is in Ohio which enabled the development team to quickly test the impact of new processes. New tooling was also required, which was also made in-house, which further reduced the development time and ensured that every option could be explored for the best result.

“If we had been working with an outside supplier, we probably would have not had the ability to fine-tune the process in the way that we did,” Mayer confirms.

That final process remains a trade secret, but JE Pistons has a patent pending for Aligned Grain Flow Technology itself – the way in which it orients the grains and structures them for increased strength.


Shown from left to right, a piston blank that has yet to be forged, a forging blank ready for CNC work, and a finish-machined forged piston. JE has full control over the manufacturing process from start to finish. 

Ultra Series Applications


JE’s Ultra Series pistons, in addition to Aligned Grain Flow Technology, feature a host of features such as premium Trend wrist pins, Perfect Skirt coating, ceramic crown coating, and premium carbon-steel ring packs.

“AFT makes the piston stronger,” Mayer concludes. “We could have gone in two directions with that. We’ve chosen to start with Ultra Series pistons that are of equal weight but stronger, for high-power, high-boost applications. But the technology would apply equally well to taking weight out of a conventional forged piston, while maintaining equal strength.”

Thanks for original info to: 

Co-ordSport are proud to be a Distributor for Race Winning Brands, which include JE Pistons and others


0 0 votes
Article Rating

Notify of

Inline Feedbacks
View all comments
Would love your thoughts, please comment.x