Introduction of Nickel Alloy Monel 400

- Oct 19, 2017-

Principal Design Features:

This alloy of nickel-copper is resistant to sea water corrosion as well as to a variety of acids and other corrosive media.


· Marine engineering

· Chemical and hydrocarbon processing equipment

· Gasoline and freshwater tanks

· Crude petroleum stills

· De-aerating heaters

· Boiler feed water heaters and other heat exchangers

· Valves, pumps, shafts, fittings, and fasteners

· Industrial heat exchangers

· Chlorinated solvents

· Crude oil distillation towers


Conventional machining techniques used for iron based alloys may be used. This alloy does work-harden during machining and has higher strength and "gumminess" not typical of steels. Heavy duty machining equipment and tooling should be used to minimize chatter or work-hardening of the alloy ahead of the cutting. Most any commercial coolant may be used in the machining operations. Water-base coolants are preferred for high speed operations such as turning, grinding, or milling. Heavy lubricants work best for drilling, tapping, broaching or boring. Turning: Carbide tools are recommended for turning with a continuous cut. High-speed steel tooling should be used for interrupted cuts and for smooth finishing to close tolerance. Tools should have a positive rake angle. Cutting speeds and feeds are in the following ranges: For High-Speed Steel Tools For Carbide Tooling Depth Surface Feed Depth Surface Feed of cut speed in inches of cut speed in inches inches feet/min. per rev. inches feet/min. per rev. 0.250" 60-70 0.030 0.250" 250-300 0.020 0.050" 90-100 0.010 0.050" 300-350 0.008 Drilling: Steady feed rates must be used to avoid work hardening due to dwelling of the drill on the metal. Rigid set-ups are essential with as short a stub drill as feasible. Conventional high-speed steel drills work well. Feeds vary from 0.0007 inch per rev. for holes of less than 1/16" diameter, 0.003 inch per rev. for 1/4" dia., to 0.010 inch per rev. for holes of 7/8"diameter. Surface speeds of 45-55 feet/minute, are best for drilling. Milling: To obtain good accuracy and a smooth finish it is essential to have rigid machines and fixtures and sharp cutting tools. High-speed steel cutters such as M-2 or M-10 work best with cutting speeds of 60 to 80 feet per minute and feed of 0.005"-0.008" per cutting tooth. Grinding: The alloy should be wet ground and aluminum oxide wheels or belts are preferred.

Cold Working:

Cold forming may be done using standard tooling although plain carbon tool steels are not recommended for forming as they tend to produce galling. Soft die materials (bronze, zinc alloys, etc.) minimize galling and produce good finishes, but die life is somewhat short. For long production runs the alloy tool steels ( D-2, D-3) and high-speed steels (T-1, M-2, M-10) give good results especially if hard chromium plated to reduce galling. Tooling should be such as to allow for liberal clearances and radii. Heavy duty lubricants should be used to minimize galling in all forming operations. Bending of sheet or plate through 180 degrees is generally limited to a bend radius of 1 T for material up to 1/8" thick and 2 T for material thicker than 1/8".


Annealing may be done at 1700 F. A stress-relief anneal may be done at 1050 F for 1 to 2 hours, followed by slow cooling.

Physical Data:

Density (lb / cu. in.)


Specific Gravity


Specific Heat (Btu/lb/Deg F - [32-212 Deg F])


Electrical Resistivity (microhm-cm (at 68 Deg F))


Melting Point (Deg F)


Poissons Ratio


Thermal Conductivity


Mean Coeff Thermal Expansion


Modulus of Elasticity Tension


Chemistry Data 









Comp. %

0.3 max

28 - 34

2.5 max

2 max


0.5 max

0.024 max