Standards Behind Stronger Surfaces: The Work of SAE’s Surface Enhancement Committees

Shot peening and related surface enhancement processes play an essential role in extending fatigue life and improving the reliability of critical components. Behind these processes is a detailed system of technical standards that defines how peening media are manufactured, how intensity and coverage are measured, how equipment is controlled, and how processing requirements are communicated throughout the supply chain.

Much of this work is performed by two SAE International technical committees: the Aerospace Surface Enhancement Committee, commonly known as ASEC, and the Surface Enhancement Committee, or SEC.

I am honored to serve as Chairperson of both committees. In this role, I work with an international group of specialists representing aerospace prime manufacturers, suppliers of Almen strips and shot peening media, equipment manufacturers, independent process experts, and shot peening service providers from around the world. My appointment as Chairperson of both committees followed the leadership of longtime friend Jack Champaigne of Electronics, Inc.

Although the committees operate within different SAE standards organizations, their work is closely connected.

The Aerospace Surface Enhancement Committee operates within SAE’s Aerospace Materials Specification organization. It was established to focus on surface enhancement technologies, including shot peening, laser peening, roller burnishing, and other mechanical surface treatments. Its principal responsibility is the development and maintenance of Aerospace Material Specifications, or AMS documents, related to these processes.

The Surface Enhancement Committee develops and maintains SAE J standards and recommended practices. These documents delineate many of the fundamental tools, definitions, and measurement methods used by the shot peening industry.

The relationship between the two committees is important. AMS specifications generally establish aerospace process, material, and production-control requirements. The J documents provide many of the standardized methods used to satisfy or verify those requirements. Maintaining consistency between the two document families is therefore essential.

The ASEC committee maintains specifications that directly affect aerospace component processing and the materials used during surface enhancement.

One of the most widely recognized documents is AMS2430, Shot Peening. This specification establishes requirements for shot peening component surfaces using metallic, glass, or ceramic media. It addresses areas such as equipment, process control, intensity, coverage, media control, masking, part handling, and inspection.

Other important aerospace documents include:

AMS2431 and its various slash sheet specifications, which establish general and material-specific requirements for controlled shot peening media. The family of slash sheets includes requirements for regular-hardness and high-hardness cast steel shot, conditioned carbon steel cut wire, stainless steel cut wire, glass bead, ceramic media, and other media classifications.

AMS2432, Shot Peening, Computer Monitored, which provides requirements for monitoring, recording, and responding to process inputs during production. Computer-monitored peening provides objective evidence that critical process settings remained within established limits throughout the operation.

AMS2590, Rotary Flap Peening of Metal Parts, which addresses portable rotary-flap peening used for localized processing, repair, and applications where conventional shot peening equipment may not be practical.

These specifications are not static documents. Equipment capabilities improve, new media become available, measurement technology changes, and experience reveals requirements that may need clarification. The committee must periodically review each specification to ensure it remains technically sound, practical to implement, and aligned with current aerospace manufacturing needs.

The Surface Enhancement Committee maintains the J documents that define many of the fundamental methods used to control shot peening.

Among the most important are:

SAE J442, which establishes requirements for the tools used in peening intensity determination and verification, including Almen strips, holders, and measuring equipment.

SAE J443, which defines procedures for deriving and verifying peening intensity. This includes the use of saturation curves and verification practices needed to demonstrate that a process is operating at the required intensity.

SAE J2277, which provides procedures for determining shot peening coverage and relating coverage to exposure time. Proper coverage is critical because both inadequate and excessive processing can adversely affect component performance.

SAE J2597, which addresses computer-generated shot peening saturation curves and provides a standardized basis for using software to evaluate intensity data.

SAE J444, which establishes standardized cast-shot and grit size designations used in blasting and shot peening.

SAE J2441, which establishes general engineering requirements for shot peening with metallic shot, glass beads, and ceramic media.

Together, these documents create a common technical language. An Almen intensity, media size, or coverage requirement must have the same fundamental meaning whether the work is being performed in Connecticut, Georgia, Europe, Asia, or any other location.

The strength of these committees comes from the range of experience represented at the table.

Aerospace prime manufacturers contribute knowledge of component design, fatigue requirements, engineering intent, and the consequences of process variation. Their representatives help ensure that specifications protect the performance and reliability of flight-critical hardware.

Almen strip and gage suppliers contribute specialized knowledge of strip manufacturing, material properties, dimensional control, calibration, and measurement repeatability.

Peening media manufacturers provide expertise in material composition, hardness, size distribution, shape, durability, manufacturing methods, and inspection.

Shot peening equipment manufacturers contribute knowledge of air-blast systems, wheel-blast systems, robotic equipment, computer monitoring, process controls, and emerging automation technologies.

Finally, shot peening processors and independent process experts contribute practical experience from the production floor. They understand how requirements are interpreted during contract review, process planning, setup, inspection, operator training, and customer or Nadcap audits.

No single organization sees every aspect of the process. A requirement that appears straightforward from a design perspective may create an unintended production or inspection problem. Conversely, a requirement that is convenient for a processor may not provide enough assurance for the designer or end user.

Committee discussion allows these viewpoints to be examined before a requirement becomes part of an industry document.

SAE standards are developed through a formal committee process. Committee members meet to discuss technical issues, prepare proposed wording, review supporting data, and resolve comments. Proposed revisions are then circulated through an established ballot process before publication. SAE serves as the neutral convener that allows participants from different organizations and countries to collaboratively develop and maintain these documents.

The chairperson’s role is not to dictate the technical outcome. Their responsibility is to keep the process moving, make sure all viewpoints are heard, encourage technically supported proposals, and help the committee reach a workable consensus.

Some revisions involve new technology. Others correct inconsistent terminology, improve inspection requirements, clarify acceptance criteria, or eliminate wording that has been interpreted differently by customers, suppliers, and auditors.

The work can be detailed and sometimes difficult. A change involving only a few words may significantly affect thousands of purchase orders, engineering drawings, internal procedures, operator instructions, and supplier approvals.

That is why proposed changes must be considered carefully.

Surface enhancement continues to evolve. Modern equipment can collect and retain significantly more process data than earlier generations of machinery. Computer monitoring, automated saturation-curve analysis, robotic motion control, electronic records, and closed-loop control systems are becoming increasingly common.

At the same time, the industry must address practical issues such as implementation periods for revised specifications, alignment between referenced documents, calibration and measurement capability, new peening-media technologies, and consistency between engineering requirements and production verification.

The committees must balance innovation with stability. Standards should encourage improved technology, but they must also remain understandable and achievable throughout a global supply chain that includes organizations of many different sizes and capabilities.

Participation in SAE standards development is both a technical responsibility and an opportunity to improve the industry.

The specifications developed by these committees affect aerospace primes, repair stations, special-process suppliers, equipment manufacturers, media producers, and thousands of operators and inspectors. More importantly, they support the reliability and fatigue performance of components used in commercial aviation, military aircraft, spacecraft, power generation, and other demanding applications.

As Chairperson of both the Aerospace Surface Enhancement Committee and the Surface Enhancement Committee, I am proud to work with professionals who are willing to contribute their time, knowledge, and experience to this effort.

Our members may represent different companies, countries, and parts of the supply chain, but we share a common objective: to develop clear, technically sound, and practical standards that advance the science and control of surface enhancement.

The work often takes place in committee meetings, technical discussions, document reviews, and ballots—and its impact can be found in virtually every properly controlled shot peening operation around the world.

Our industry relies on published specifications and standards. 

The Standards Forum shares and reviews these standards.