Your Jaw Plates Are Costing You More Than You Think
You replace the jaw plates. Three weeks later, the fixed jaw is visibly worn—again. Or you spec in a harder alloy to “last longer,” and within days it cracks, taking a weekend shutdown and an emergency order with it.
The root cause is almost never the brand. It’s the wrong material for the job.
Most operations pick jaw plate alloys the way they order spare parts: habit, lowest price, or whatever the last supplier recommended. That approach works—until it doesn’t.
This guide cuts through the guesswork. You’ll get:
- A clear explanation of the 2 properties that define jaw plate performance
- A breakdown of 5 industry-standard alloys with OEM cross-references (Metso, ESCO, Sandvik)
- A 3-step selection method you can apply to your operation today
- A ready-to-use material-vs-application selection table
- The 5 most common selection mistakes—and how to avoid them
No filler. Just the information you need to stop replacing jaw plates too often.
The Only 2 Properties That Actually Matter
Two properties determine whether a jaw plate lasts three weeks or three months.
1. Impact Resistance
Impact resistance is the jaw plate’s ability to absorb sudden, high-force blows without cracking or chipping.
This matters most when you’re processing:
- Large run-of-mine (ROM) feed with oversize boulders
- Hard granite, basalt, or quartzite in primary crushing
- Recycled concrete or demolition material containing rebar
Low impact resistance = cracked jaw plates, broken teeth, potential damage to the crusher frame itself.
2. Abrasion Resistance
Abrasion resistance is the jaw plate’s ability to resist surface wear as material continuously grinds and slides across it.
This matters most when you’re processing:
- High-silica rock (quartzite, flint, silica sand)
- Fine, sandy, or dirty feed material
- Abrasive limestone in secondary or tertiary positions
Low abrasion resistance = jaw plates that wear down fast, lose tooth profile, and need frequent replacement.
The Core Trade-Off
Higher manganese content = faster work-hardening = better abrasion resistance, but lower impact toughness.
Lower manganese content = higher toughness = better impact resistance, but faster surface wear in abrasive conditions.
There is no single “best” jaw plate alloy. There is only the alloy that matches your feed material, your crusher size, and your application.
5 Industry-Standard Jaw Plate Alloys: Full Breakdown
Quick Comparison Table
| Alloy | Mn Content | Impact Resistance | Abrasion Resistance | Best For | OEM Reference |
| Standard Mn Steel | ~14% | ★★★★★ | ★★☆☆☆ | Soft rock, recycled material, low-abrasion feeds | ESCO 14HN, EvoQuip 14% Mn |
| High Mn Steel | ~18% | ★★★★☆ | ★★★☆☆ | General mining, limestone, mixed feeds | Metso XT710, ESCO 14HN, EvoQuip 18% Mn |
| Ultra-High Mn Steel | ~22% | ★★★☆☆ | ★★★★★ | Highly abrasive hard rock (granite, quartzite, basalt) | ESCO 14RH, EvoQuip 22% Mn |
| High-Alloy Austenitic Steel | Varies | ★★★★☆ | ★★★★☆ | Medium-to-hard abrasive rock, large crushers | Metso C-series high-alloy austenitic, Sandvik M2 / M8 |
| TiC Composite (Mn base + TiC) | 18–22% base | ★★★★☆ | ★★★★★+ | Extreme abrasion, high-silica rock, wide-tooth jaws | Metso MX Jaw (hybrid technology) |
Alloy 1: Standard 14% Manganese Steel — The Entry-Level Option
Composition: ~1.1% C, 13–14% Mn, trace Cr
How it works: Work-hardening is slower with 14% manganese. The surface hardens gradually as it absorbs impact, which is ideal when feed forces are moderate.
Best applications:
- Soft limestone, sandstone, coal
- Recycled concrete and asphalt (without heavy rebar)
- Secondary crushing positions
- Mobile crushers in low-abrasion environments
14% Mn is tough, crack-resistant, and cost-effective for soft feeds. The trade-off is wear rate: put it against granite or high-silica rock and it won’t last. Think of it as the right tool for a specific job—not a universal solution.
OEM reference: ESCO 14HN (standard alloy for general crushing), EvoQuip 14% Mn (on-request option)
Soft feed, mobile plant, and you need maximum crack resistance without paying for abrasion resistance you don’t need? This is your alloy.
Alloy 2: High Manganese Steel 18% — The Industry Workhorse
Composition: ~1.2% C, 17–19% Mn, 1–2% Cr
How it works: 18% manganese is the global standard for jaw crusher wear parts. It balances toughness and abrasion resistance well enough to cover the majority of primary crushing applications in mining, quarrying, and cement production.
Best applications:
- Hard limestone, dolomite, granite (moderate abrasion)
- Primary jaw crushing in mines
- Mixed feed with occasional oversize
- Most mobile and stationary crushing plants
It’s not the best at anything—but it’s good enough at everything. That’s why it’s the default choice for the majority of mining operations worldwide. It won’t win in extreme conditions: very high-silica feeds will wear it faster than 22% Mn, and severe single-blow impact loads are better handled by 14% Mn. But for the vast middle ground of real-world crushing applications, 18% Mn is where you start.
OEM reference: Metso XT710 (standard alloy for C-series jaw crushers), ESCO 14HN, Sandvik M1 (standard alloy with high shock and impact resistance), EvoQuip 18% Mn (default for all jaw models)
When to choose it: The majority of mining and quarry operations will perform well with 18% Mn. If you’re unsure, start here.
Alloy 3: Ultra-High Manganese Steel 22% — The Hard Rock Specialist
Composition: ~1.3% C, 20–22% Mn, 2–3% Cr
How it works: Ultra-high manganese work-hardens faster and achieves a deeper hardened surface layer under impact. This makes it significantly more abrasion-resistant than 18% Mn in conditions where rock continuously abrades the jaw surface.
Best applications:
- Highly abrasive hard rock: granite, quartzite, flint, basalt
- High-silica feeds (>65% SiO₂)
- Primary crushing of blasted rock with high fines content
- Cement plant feeding on hard limestone
In the right application, 22% Mn can cut your change-out frequency in half compared to standard 18% Mn. The catch: that higher manganese content comes with lower impact toughness. If your feed regularly delivers large, irregular boulders with severe single blows, 22% Mn may chip or crack where 18% Mn would flex. Use it when abrasion is your dominant wear mechanism—not when impact is.
OEM reference: ESCO 14RH (extra-high manganese), Sandvik M2 / M8 (high resistance to abrasive rock), EvoQuip 22% Mn (for abrasive applications)
When to choose it: Your rock has a silica content above 50%, or you’re crushing granite, quartzite, or basalt in a primary position.
Alloy 4: High-Alloy Austenitic Steel — The Large Crusher Upgrade
Composition: Proprietary austenitic steel matrix with alloying additions (Cr, Mo, Al depending on grade)
How it works: Austenitic steel alloys are engineered for a specific balance: tougher core than standard Mn steel, with a harder, more wear-resistant surface. They are particularly effective in large-format jaw crushers where jaw plate mass and stress distribution are different from smaller machines.
Best applications:
- Large jaw crushers (C110 and above, CJ412 and above)
- Medium-to-hard abrasive feeds
- Operations that need a longer-lasting alternative to standard Mn without going to TiC composite pricing
High-alloy austenitic grades deliver 1.5–2.5x the wear life of standard AR steel, and they do it with a better-balanced toughness profile than basic Mn in large crusher applications. The trade-off is cost and availability—these grades are priced above standard Mn and not as widely stocked. For operations that need a meaningful step up from 18% Mn without committing to TiC composite pricing, this is the logical next rung.
OEM reference: Metso high-alloy austenitic jaw plate range for C-series (note: Metso’s Fatboy uses the same material but is a cheek plate, not a jaw plate), ESCO 14G (aluminium-bearing alloy—highest abrasion resistance in the ESCO manganese range, optimized for extreme abrasive wear), ESCO 14L (standard for thick castings), Sandvik M2 / M8 (Note: Sandvik M2 covers both 22% Mn and high-alloy austenitic applications depending on crusher model—check with your Sandvik distributor to confirm the correct grade for your specific machine.)
When to choose it: You run a large-format crusher on medium-to-hard abrasive material and need a step up from standard 18% Mn without the full cost of composite technology.
Alloy 5: TiC Composite Jaw Plate — Maximum Wear Life
Composition: 18–22% Mn steel matrix with titanium carbide (TiC) inserts embedded in the high-wear zones
How it works: Titanium carbide (TiC) has a Vickers hardness of approximately 3,200 HV—many times harder than manganese steel. When embedded into the jaw plate at the surface wear zones, TiC particles form an extremely hard working layer while the Mn steel matrix maintains toughness underneath. The result is a jaw plate that resists surface wear at a fundamentally different level.
Best applications:
- Highly abrasive hard rock crushing (granite, quartzite, silica-rich material)
- Wide-tooth jaw plate profiles where tooth wear is concentrated
- Operations with extremely high cost-of-downtime (large open-pit mines, cement plants with tight production schedules)
The upfront cost is the highest of any option on this list. But in the right application—highly abrasive feed, frequent change-outs, significant downtime cost—TiC composite delivers the lowest cost-per-operating-hour. The limit is impact: if severe single blows dominate your feed conditions, TiC surface layers can fracture. This is a tool for abrasion-dominated environments, not impact-dominated ones. Availability is also more limited than standard Mn grades, and lead times are typically longer.
OEM reference: Metso MX Jaw (hybrid manganese + proprietary wear-resistant surface material, quoted at up to 2–3x standard jaw plate life in abrasive applications)
When to choose it: You’re crushing highly abrasive material, changing jaw plates monthly, and your downtime cost is significant. The unit cost is higher, but the cost-per-operating-hour is lower.
3-Step Selection Process: Choose the Right Alloy Every Time
You don’t need to memorize every alloy specification. You need to answer three questions.
Step 1: What Is Your Feed Material?
| Feed Type | Silica Content | Abrasion Level | Recommended Alloy |
| Soft limestone, sandstone, coal | Low (<30% SiO₂) | Low | 14% Mn or 18% Mn |
| Medium limestone, dolomite | Moderate (30–50% SiO₂) | Moderate | 18% Mn |
| Hard limestone, medium granite | Moderate–High (50–65% SiO₂) | Moderate–High | 18% Mn or 22% Mn |
| Granite, quartzite, basalt | High (>65% SiO₂) | High | 22% Mn or TiC Composite |
| Recycled concrete / demolition | Variable | Low–Moderate (but high impact) | 14% Mn or 18% Mn |
| Cement plant hard feed | High | High | 22% Mn or High-Alloy Austenitic |
Step 2: What Is Your Application?
| Application | Key Consideration | Alloy Adjustment |
| Primary crushing (ROM feed, large boulders) | Impact loading is severe | Prioritize toughness → 14% or 18% Mn |
| Secondary crushing (pre-crushed feed) | Abrasion dominant | Prioritize wear resistance → 18% or 22% Mn |
| High fines content in feed | Accelerates abrasive wear | Upgrade Mn content, consider TiC for wide teeth |
| Presence of steel (rebar, tramp iron) | Severe impact risk | 14% Mn, high toughness required |
| Large crusher (C110+, CJ412+) | Different stress distribution | Consider two-piece jaw plates, High-Alloy Austenitic |
Step 3: What Is Your Cost Priority?
| Priority | Approach | Best Alloy Choice |
| Lowest unit cost | Basic Mn grade, replace as needed | 14% or 18% Mn |
| Best cost-per-ton | Match alloy to feed, reduce change-outs | 18% or 22% Mn correctly specified |
| Lowest total cost of ownership | Maximize service life, minimize downtime | TiC Composite or High-Alloy Austenitic |
5 Selection Mistakes That Cost Operations Money
Mistake 1: Using a Hard Alloy in Primary Crushing With Oversize Feed
High-chrome iron and overly hard alloys have excellent abrasion resistance—but they lack the toughness to handle large, irregular feed.
In primary crushing, jaw plates regularly absorb shock loads from boulders and blasted rock. A brittle alloy will chip or crack, sometimes in the first week. Stick to 18% Mn or 14% Mn for primary positions with severe impact exposure.
Mistake 2: Running 14% Manganese on Granite
Standard 14% manganese steel is designed for toughness, not abrasion resistance. Against high-silica hard rock, it can wear through in 10–15 operating days.
If your feed is granite, quartzite, or any rock with silica content above 50%, you need at least 18% Mn—and likely 22% Mn or higher.
Mistake 3: Changing Material When You Should Change Tooth Profile
Material selection matters. But so does tooth geometry.
If your jaw plates are wearing unevenly—heavy wear at the bottom, fast tooth rounding—the problem may be that fine material is packing into the crushing chamber. No alloy upgrade will fix a geometry mismatch. Screen your fines before the jaw, or switch to a wider tooth profile first.
Mistake 4: Buying on Price Without Checking Manganese Content
In the aftermarket, not all “18% Mn” jaw plates are equal. Some suppliers reduce actual manganese content to cut costs while marketing the product as standard grade. The result: a jaw plate that looks identical but wears significantly faster.
Always ask for a material certificate (heat certificate) from your supplier. A valid certificate should confirm: actual Mn%, C%, and Cr% per heat or batch, the heat number for traceability, and the testing method used (ASTM A128 or equivalent). If a supplier can’t provide this, treat it as a red flag—not a negotiating point.
Mistake 5: Using the Same Alloy for Both Fixed and Swing Jaw
The fixed jaw and the swing jaw experience different wear patterns.
The swing jaw typically wears faster at the bottom; the fixed jaw wears more evenly across the profile. In large crushers especially, running different alloy grades or rotating the plates at different intervals—rather than replacing both simultaneously—can significantly reduce material cost and extend overall plate life.
Boost Jaw Plate Life by 30%: Material + Tooth Profile Pairing
Alloy selection is half the equation. Tooth profile is the other half. The right combination can significantly extend service life compared to running the wrong profile with the right alloy.
| Feed Condition | Recommended Alloy | Recommended Profile | Why It Works |
| High-abrasion hard rock (granite, quartzite) | 22% Mn or TiC Composite | Coarse Corrugated (CC) | Coarse corrugated teeth distribute impact force across a larger surface area, reducing peak stress per tooth. In high-abrasion conditions, field data consistently shows meaningful wear rate reduction compared to standard tooth profiles. |
| High fines content | 22% Mn or High-Alloy Austenitic | Wide Teeth (WT) | Wide tooth spacing prevents fine material from packing and locking at the bottom of the crushing chamber—a primary cause of accelerated base wear. Operations using wide teeth in high-fines environments typically report meaningfully longer plate life compared to standard profiles. |
| Primary ROM feed, mixed sizes | 18% Mn | Sharp Teeth (ST) or Corrugated | Sharp teeth grip irregular feed more effectively, reducing slippage and improving breakage efficiency. This means less re-circulation of unbroken material and more consistent throughput. |
| Recycled concrete / demolition | 14% Mn | Super Grip or Multi-Tooth | Multi-tooth profiles maximize contact area on flat, smooth surfaces (typical of concrete slabs), while the 14% Mn base absorbs rebar and steel fragment impacts without chipping. |
| Large crusher (C110+, CJ412+) | High-Alloy Austenitic or 22% Mn | Two-piece jaw plate | Two-piece plates allow independent rotation of upper and lower sections. Based on field experience, bottom wear typically runs 40–60% faster than the top, which means premature full-plate replacement on both sides. Rotating independently prevents this and can reduce annual jaw plate consumption by 20–30%. |
Pro tip for large crusher operations: Two-piece (split) jaw plates—as used on Metso C110 and above—allow you to rotate the upper and lower sections independently. Based on field experience, bottom wear typically runs 40–60% faster than the top. This alone can reduce jaw plate consumption by 20–30% annually.
Choose the Right Jaw Plate Alloy — Summary
Jaw plate selection isn’t complicated once you understand the fundamentals.
The short version:
- 14% Mn→ soft feed, high impact, recycled material
- 18% Mn→ the universal starting point, covers the majority of applications
- 22% Mn→ high-abrasion hard rock, granite, quartzite, high-silica cement feeds
- High-Alloy Austenitic→ large crusher upgrade, balanced abrasion + toughness
- TiC Composite→ extreme abrasion, maximum service life, lowest cost-per-ton in demanding conditions
Match your alloy to your material. Match your tooth profile to your feed conditions. And always verify chemistry with a material certificate before you commit to a supplier.
The right jaw plate doesn’t just last longer. It reduces downtime, lowers your cost-per-ton, and keeps your plant running on schedule.
Get a Jaw Plate Recommendation for Your Operation
Not sure which alloy is right for your feed material or crusher model?
Tell us your material type and crusher model — we’ll give you a custom alloy recommendation, free.
Need a quote on Metso- or Sandvik-equivalent jaw plates? Contact us for a dedicated cost comparison against your current OEM pricing.
We work with operations running Metso C-series, Sandvik CJ-series, Terex Premiertrak, ESCO-specified equipment, and more. Every quote comes with verified chemistry and full material traceability—so you know exactly what you’re installing.
