MAN-CRO® Abrasion Resistant Steel Plate

MAN-CRO® 400F, 450F AND 500F

MAN-CRO AR grades are premium quality alloy steels designed to provide the greatest combination of hardness, abrasion resistance, toughness, weldability and formability.

By desulphurizing and degassing during manufacturing, we are able to offer a “clean” alloy. This process provides good cold forming characteristics and impact properties to temperatures as low as -40°F, while still maintaining good weldability. High pressure water spray-quench ensures maximum scale removal and enhances welding processes.

Man-Cro Abrasion Resistant Steel Plate Plate

Available Stock Sizes

GRADE Thickness Width Lengths
MAN-CRO 400F 3/16″ to 3″ 48″ to 96″ up to 288″
MAN-CRO 450F 1/4″ to 3″ 48″ to 96″ up to 288″
MAN-CRO 500F 1/4″ to 3″ 48″ to 96″ up to 288″
GRADE Thickness Width Lengths
MAN-CRO 400F 1/4″ to 2″ 1″ to 12″ up to 288″
MAN-CRO 450F Custom Cut
MAN-CRO 500F Custom Cut


  • Maximum Abrasion & Impact Resistance
  • Excellent Weldability
  • Cold Formability
  • Excellent Charpy Impact Properties
  • Nickel Alloy Provides Deeper Hardening
  • Flat Surface
  • “Clean” Steel
  • Demagnetization Available
  • St. Lawrence Custom Fabrication Available
  • Fine Grain Structure
  • Made in USA
Man-Cro Wear Resistant Steel Plate

Chemistry (typical %)

Manufactured in Compliance with ISO 9002 ABS-QE

GRADE C Si Mn P S Cr Ni Mo B
MAN-CRO 400F .12-.20 .35-.55 1.55* .025* .015* .55* 1.0* .55* .0005-.005
MAN-CRO 450F .20-.25 .35-.55 1.55* .025* .015* .55* 1.0* .65* .0005-.005
MAN-CRO 500F .25-.31 .35-.55 1.55* .025* .015* .75* 1.5* .65* .0005-.005

*max %

Steel Plate Comparison

Product Abrasion Resistance Impact Resistance Weldability Machinability Forming Cutting
MAN-CRO 450F G - VG G G M - F F - G G - VG
Ultra-Met Standard E G E(1) M(2) F G(4)
Ultra-Met Impact VG G - VG E(1) M(2) M - F G(4)
Ultra-Met Abrasion E - S G E(1) M(2) F G(4)
Hardlite E G E(1) M(2) F G(4)
SLS 14% Manganese F E VG(3) M G G

S: Superior, E: Excellent, VG: Very Good, G: Good, F: Fair, M: Marginal

(1) Carbon Base Only

(2) EDM, Plasma or Air Arc holes only

(3) When welding Manganese to any other metal, use 309 or 310 SS electrode w/ minimum heat input

(4) Plasma, waterjet or laser


We recommend the use of St. Lawrence's fabrication services to eliminate processing and fabrication errors.


Plasma cutting is recommended, but all MAN-CRO grades may be gas cut with conventional fuels and procedures. MAN-CRO should be cut at minimum room temperature or preferably in a preheat range of 200˚- 400˚F to prevent surface or edge cracking. If machining is required near torch cut edges, allow sufficient stock removal to get below hardened edge or preheat to 400˚F prior to flame cutting.


The low level of oxides and sulfides present in MANCRO grades provides superior bending properties. Bending force required is approximately 4X carbon steel grades. 3t (transverse) is usually the minimum radius for MAN-CRO 400F up to 3/4˝ thick plate, 6t (transverse) for MAN-CRO 450F up to 3/4˝ thick plate and 10t (transverse) for MAN-CRO 500F up to 1/2˝ thick plate.


High speed steels, cobalt or cemented carbide can be used for planing, cutting, drilling and countersinking. Reducing speeds depending on plate hardness are recommended. Use a top angle (included) of 150˚ and edge clearance of 5°-7°.


Welding of Hardlite can be accomplished by joining of the carbon steel base material using a low hydrogen welding rod or wire. No preheating is required. When welding two pieces of Hardlite, bevel base plate (underside) and complete using normal welding procedure. Can be field pierced with covered metal electrodes; Chamfer-Trode, Rocket Groove, Cut-Trode or equivalents.

1) General Instructions

MAN-CRO grades can be welded with standard low hydrogen electrodes or wire. Submerged-arc, metal-arc and gas-shielded metal-arc (TIG) are recommended. Original mechanical properties can be maintained by using low heat input methods. To insure good welding results, be sure joint is clean and use only dry consumables.

2) Preheating

The pre-heat and interpass temperature should be maintained throughout welding procedure. Temperature crayons are helpful in maintaining reasonably constant temperature during welding. Under severe restraint conditions, tack welding or in damp weather, increase pre-heat temperatures by 25%.

3) Consumables

Filler metal with lower tensile and yield strength are recommended in welding MAN-CRO. This type of material provides more ductility while the weld is cooling, thus reducing stress on the joint. AWS E70XX, E80XX and E90XX shielded metalarc electrodes have been successful for submerged-arc and gas metal arc wire. Low hydrogen flux is also recommended. For a butt weld, when the joint strength must be equal to that of the parent plate, electrodes equivalent to AWS E 11018 are recommended.


Plate Thickness Range
GRADE .5″ 1″ 1.5″ 2″ 2.5″ 3″
MAN-CRO 400F 60°F Min 300°F
MAN-CRO 450F 60°F Min 300°F
MAN-CRO 500F 300°F 375°-425°F

Service comparisons Abrasion test

Man-Cro BNH Hardness

Charpy impact properties

Test Section .5″– 2.5″ THK

Man-Cro Energy Absorbed