ASTM A193
Grade B8MLN / B8MLNA
SS 316LN Bolts
Why Molybdenum Genuinely Matters Here
B8LN, built on 304LN, already combines low-carbon weld-decay resistance with nitrogen-recovered strength — a genuinely useful combination covered on our B8LN grade page. But 304-series stainless, with or without nitrogen, was never designed with strong chloride resistance in mind.
B8MLN and B8MLNA exist specifically to add that missing piece — the base material shifts from 304LN to 316LN, and that single change, a deliberate 2–3% molybdenum addition, is what genuinely improves resistance to pitting and crevice corrosion in chloride-rich environments like seawater, de-icing salts, and many industrial chemical process streams. Everything else about the grade’s logic — low carbon for weld-decay resistance, nitrogen for recovered strength — carries over unchanged from the 304LN-based grade.
That’s the entire reason a buyer chooses B8MLN over B8LN — not a difference in weld-decay resistance or general mechanical approach, but a genuine, specific answer to chloride exposure that the 304-series base material was never built to handle as well.
Akbar Fasteners Pvt. Ltd. exports to over 50 countries, and our B8MLN and B8MLNA stud bolt range is verified by chemical composition and mechanical testing under our ISO 9001:2015 quality system.
Where This Grade Genuinely Applies
Genuine Chloride & Pitting Resistance
Molybdenum content delivers real resistance to chloride-driven pitting and crevice corrosion.
Same Weld-Decay Resistance as B8LN
Low-carbon composition removes chromium carbide precipitation risk during welding.
Correct Choice for Marine & Chloride Service
Reliable where seawater, de-icing salts, or chloride-bearing process chemistry are present.
Verified Chemical & Mechanical Properties
Batch testing confirms genuine molybdenum and nitrogen content for the ordered grade.
B8MLN vs B8MLNA — Side by Side
ASTM A193 Grade B8MLN
Solution-annealed condition, offering the base mechanical properties of molybdenum-bearing, nitrogen-enhanced SS 316LN without additional cold-working for strength.
Moderate Strength, Full Ductility →ASTM A193 Grade B8MLNA
Strain-hardened (cold-worked) condition of the same base material, delivering genuinely higher tensile and yield strength than B8MLN at a modest reduction in ductility.
Higher Strength, Slightly Reduced Ductility →B8LN vs B8MLN — Quick Reference
Confirming whether chloride exposure is genuinely present decides which of these two closely related grades fits. This table is the quick reference we use with buyers before quoting.
| Aspect | Grade B8LN (304LN) | Grade B8MLN (316LN) |
|---|---|---|
| Molybdenum Content | None | ~2–3% |
| Chloride / Pitting Resistance | Standard | Genuinely improved |
| Weld-Decay Resistance | Excellent | Excellent, same mechanism |
| Best Suited For | General welded, non-chloride service | Marine, chloride-bearing, or de-icing salt exposure |
B8MLN / B8MLNA Specification Details
Nominal Composition
- Chromium 16.0 – 18.0%
- Nickel 10.0 – 14.0%
- Molybdenum 2.0 – 3.0%
- Carbon / Nitrogen ≤0.03% / Controlled Addition
Typical Mechanical Range
- B8MLN Tensile ~515 MPa Min
- B8MLNA Tensile ~690 MPa Min
- B8MLN Yield ~205 MPa Min
- B8MLNA Yield ~450 MPa Min
Fastener Types We Manufacture
- Stud Bolts Continuous & Double-End
- Hex Bolts Standard & Heavy Hex
- Matching Nuts ASTM A194 Grade 8MLN
- Custom Sizes On Request
Application Areas
Wherever weld-decay resistance and genuine chloride resistance are both needed together.
Marine & Offshore Structures
bolting with recovered strength
Coastal & De-Icing Salt Exposure
and roadway environments
Chemical Process Equipment
chloride-bearing process chemistry
Desalination Plant Equipment
welded bolting
LNG & Cryogenic Marine Equipment
combined exposure
Pulp & Paper Chloride-Bearing Process
chloride exposure
Welded Piping in Coastal Refineries
weld exposure together
General Welded Marine-Grade Bolting
needing chloride and weld resistance
Standard Export Documentation
Prepared as standard practice for every B8MLN / B8MLNA bolt shipment.
Mill Test Certificate (MTC)
Heat number, chemical composition, and mechanical property verification for every lot.
Chemical Composition Report
Confirms actual molybdenum and nitrogen content fall within the specified 316LN grade range.
Certificate of Conformance
Confirms the shipment matches the purchase order grade/size specification in full.
Certificate of Origin (COO)
Confirms India as country of manufacture for destination customs purposes.
NABL Accredited Test Reports
Independent mechanical, dimensional, and corrosion testing available on request.
Commercial Invoice & Packing List
Itemized value, Incoterm, and detailed carton/weight breakdown for customs clearance.
Internationally Recognised Standards Coverage
Related Fastener Grades & Materials
ASTM A193 Grade B8LN
Our 304LN-based counterpart, without molybdenum’s added chloride resistance.
View Grade B8LN →ASTM A193 Grade B8CLN / B8CLNA
Our niobium-stabilized counterpart grade family, based on 347LN.
View B8CLN / B8CLNA →SS 316 / 316H / 316L Fasteners
Our broader 316 family guide, covering the marine-grade logic B8MLN builds on.
View SS 316 Guide →Stainless Steel Fasteners Manufacturer India
Our broader stainless steel fastener manufacturing capability across all major grades.
View SS Manufacturer Guide →Chloride Exposure?
We’ll Confirm the Right Grade
Tell us your service environment and strength needs — we’ll confirm whether B8MLN or B8MLNA genuinely fits or whether the 304LN-based B8LN is sufficient, and quote with full documentation. Akbar Fasteners Pvt. Ltd. responds within 24 hours.
Sales: +91 724 0000 733 · Support: +91 800 9315 333 · sales@akbarfasteners.in
