When it comes to shot blasting and surface preparation, one of the most important factors is choosing the right abrasive media. Among them, steel shots are the most widely used due to their durability, recyclability, and ability to deliver uniform cleaning and strengthening. But for engineers, buyers, and quality inspectors, it’s not enough to simply know what steel shots are—the real value lies in understanding their specifications.
Steel shots specification refers to the technical parameters of steel shot abrasives, including size classification (S70–S780), hardness levels (40–65 HRC), chemical composition (high-carbon, low-carbon, stainless steel), and compliance with standards such as SAE J827 and ISO 11124.
If you came just to learn the quick definition above, now you know the basics. But if you want to make the right decisions in procurement, process design, or quality control, you need a deeper understanding of the size chart, hardness range, composition, and international standards that define steel shots.
Steel shots specification is the foundation of reliable surface preparation, ensuring that every blasting process delivers the expected cleanliness, coating adhesion, and durability.
Table of Contents
Why Do Steel Shots Specifications Matter?
Specifications are more than numbers on a datasheet — they determine cleaning efficiency, abrasive lifespan, and coating performance. Without proper specifications, blasting can lead to wasted media, surface damage, or premature coating failure.
Steel shots specifications matter because they control the blasting outcome, from rust removal and descaling efficiency to coating adhesion and long-term durability.
Industries such as automotive, aerospace, shipbuilding, and foundries depend on strict adherence to steel shot specifications. For example, a shipyard requires larger S390 – S660 shots for hull cleaning, while aerospace manufacturers use fine S70 – S110 shots with precise hardness for peening.
Understanding specifications is the key to choosing the right abrasive for each application.
How Are Steel Shots Sizes Classified?
The most common way to classify steel shots is by SAE size numbers, ranging from S70 to S780, each corresponding to a specific diameter in millimeters.
Steel shots sizes are classified from S70 (0.18–0.30 mm) to S780 (2.00–2.80 mm), based on SAE J444 sieve standards. Smaller shots are used for precision work, while larger shots are suited for heavy-duty cleaning.
| SAE Size | Diameter Range (mm) | Typical Applications |
| S70 | 0.18–0.30 | Aerospace, precision peening |
| S110 | 0.28–0.50 | Automotive gears, springs |
| S230 | 0.60–0.85 | General descaling, cleaning |
| S390 | 1.00–1.40 | Bridge steel, heavy coating removal |
| S660 | 1.70–2.36 | Ship hull cleaning, construction beams |
| S780 | 2.00–2.80 | Large castings, forging desanding |
The steel shots size chart provides the first benchmark for selecting the right abrasive in any shot blasting process.
What Are the Hardness Specifications of Steel Shots?
Hardness directly affects the impact energy, cleaning speed, and abrasive life cycle of steel shots.
Steel shots hardness ranges from 40–65 HRC: 40–50 HRC for general cleaning, 50–60 HRC for heavy descaling, and 60+ HRC for aggressive coating removal.
- 40–50 HRC: Standard cleaning, longer abrasive life.
- 50–60 HRC: Balanced performance, faster scale removal.
- 60–65 HRC: Aggressive cleaning, shorter life, used in shipbuilding and heavy industry.
The right hardness ensures cost efficiency and surface quality, balancing cleaning power with abrasive durability.
What Is the Chemical Composition of Steel Shots?
Composition defines the mechanical properties, toughness, and corrosion resistance of steel shots.
Steel shots are mainly high-carbon (0.8–1.2% C) or low-carbon (0.1–0.2% C), with stainless steel variants (304/430) used for non-ferrous or contamination-sensitive applications.
| Chemical Composition | High-Carbon Steel Shot | Low-Carbon Steel Shot |
| C | 1.010% | 0.1510% |
| Si | 0.620% | 0.1250% |
| Mn | 0.714% | 0.4320% |
| S | 0.025% | 0.0090% |
| P | 0.022% | 0.0190% |
- High-Carbon Steel Shots: 0.80–1.20% C, tough, widely used.
- Low-Carbon Steel Shots: 0.10–0.20% C, softer impact, less substrate stress.
- Stainless Steel Shots (304/430): Non-rusting, used for stainless steel, aluminum, food/medical equipment.
Choosing the right chemical composition ensures both performance and material compatibility.
Which International Standards Define Steel Shots?
Steel shots are manufactured and certified under globally recognized standards.
The main steel shots standards are SAE J827/J444, ISO 11124-3, GB/T 18838 (China), and EN 12413 (Europe), defining size, hardness, and chemical composition.
- SAE J827 / J444: US standards for size and hardness.
- ISO 11124-3: International metallic abrasives standard.
- GB/T 18838: Chinese standard.
- EN 12413: European safety standard.
Compliance with ISO and SAE standards guarantees global acceptance of steel shots specifications.
How Do Applications Vary by Specification?
Different industries use different sizes, hardness, and compositions of steel shots.
Automotive uses small shots for peening, shipbuilding uses large high-hardness shots for hull cleaning, aerospace demands precise controlled hardness, and foundries use heavy shots for casting desanding.
| Industry | Specification Example | Application |
| Automotive | S110–S230, 40–50 HRC | Peening, cleaning gears & springs |
| Shipbuilding | S390–S660, 50–60 HRC | Hull plate descaling & coating prep |
| Aerospace | S70–S110, precise hardness | Shot peening for fatigue resistance |
| Foundry | S390–S780, high hardness | Sand removal from castings |
Application-based selection ensures both performance and compliance.
How to Read a Steel Shots Specification Sheet?
A steel shots specification sheet summarizes the essential parameters buyers and inspectors need.
A steel shots specification sheet includes size distribution, hardness, chemical composition, density, microstructure, and compliance with SAE/ISO standards.
Key elements:
- Size range & sieve analysis.
- Hardness values.
- Chemical composition.
- Microstructure (tempered martensite).
- Density (≥7.0 g/cm³).
- Durability (recycling life).
- Standards certification.
Reading specifications correctly prevents certificate fraud and ensures true compliance with standards.
Conclusion
The steel shots specification is the benchmark for quality and performance in every shot blasting process. By understanding size classifications, hardness ranges, chemical composition, and international standards, industries can make informed decisions that ensure durability, efficiency, and coating reliability.
Proper specification is the foundation of cost-effective, reliable, and globally compliant surface preparation.
At BH, we supply ISO- and SAE-certified steel shots, grits, and stainless abrasives, with complete specification sheets covering size, hardness, and chemical composition.
Contact us today for a free datasheet or sample, and let us help you select the right abrasive for your application.