Monel Flat Washers - Corrosion-Resistant Nickel-Copper Alloy Washers

Monel flat washers are made from a nickel-copper alloy renowned for its exceptional corrosion resistance in seawater, hydrofluoric acid, and other aggressive chemical environments. They are the preferred choice for marine, chemical processing, and offshore applications where stainless steel is insufficient.

Superior Washer & Gasket Corp manufactures Monel washers in standard and custom sizes with ISO 9001:2015 certified quality control. Our specialty metal washer capabilities include Monel, Inconel, phosphor bronze, and other high-performance alloys-all made in the U.S.A. with material certifications available.

Nickel-copper Monel alloy for superior corrosion resistance
Ideal for marine and chemical processing environments
Standard and custom Monel washer sizes
ISO 9001:2015 certified manufacturing
Made in the U.S.A.; certifications available

Showing 1–50 of 98 products

SKU	ID	OD	Thickness	Material	ID TOL	OD TOL	Quantity
910-10-040	ID 0.065	OD 0.187	Thickness 0.04	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-100-125	ID 1.062	OD 2.0	Thickness 0.125	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-101-125	ID 1.062	OD 2.5	Thickness 0.125	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-102-100	ID 1.188	OD 2.0	Thickness 0.1	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-103-140	ID 1.25	OD 2.75	Thickness 0.14	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-104-140	ID 1.375	OD 3.0	Thickness 0.14	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-105-187	ID 1.5	OD 3.25	Thickness 0.187	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-106-187	ID 1.562	OD 3.25	Thickness 0.187	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-107-061	ID 0.27	OD 0.497	Thickness 0.061	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-108-062	ID 0.285	OD 0.735	Thickness 0.062	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-11-025	ID 0.068	OD 0.125	Thickness 0.025	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-12-025	ID 0.068	OD 0.187	Thickness 0.025	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-13-025	ID 0.068	OD 0.25	Thickness 0.025	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-14-020	ID 0.078	OD 0.187	Thickness 0.02	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-15-025	ID 0.084	OD 0.156	Thickness 0.025	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-16-031	ID 0.093	OD 0.25	Thickness 0.031	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-17-020	ID 0.093	OD 0.437	Thickness 0.02	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-18-031	ID 0.109	OD 0.312	Thickness 0.031	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-19-032	ID 0.125	OD 0.25	Thickness 0.032	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-20-031	ID 0.125	OD 0.312	Thickness 0.031	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-21-040	ID 0.125	OD 0.375	Thickness 0.04	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-22-031	ID 0.125	OD 0.406	Thickness 0.031	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-23-040	ID 0.141	OD 0.406	Thickness 0.04	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-24-031	ID 0.147	OD 0.375	Thickness 0.031	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-25-031	ID 0.156	OD 0.312	Thickness 0.031	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-26-040	ID 0.156	OD 0.375	Thickness 0.04	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-27-040	ID 0.156	OD 0.438	Thickness 0.04	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-28-031	ID 0.172	OD 0.375	Thickness 0.031	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-29-031	ID 0.174	OD 0.437	Thickness 0.031	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-30-040	ID 0.187	OD 0.343	Thickness 0.04	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-31-040	ID 0.187	OD 0.375	Thickness 0.04	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-32-040	ID 0.187	OD 0.438	Thickness 0.04	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-33-040	ID 0.187	OD 0.5	Thickness 0.04	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-34-109	ID 0.187	OD 2.0	Thickness 0.109	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-35-062	ID 0.2	OD 0.625	Thickness 0.062	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-36-031	ID 0.203	OD 0.437	Thickness 0.031	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-37-040	ID 0.203	OD 0.562	Thickness 0.04	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-38-031	ID 0.218	OD 0.437	Thickness 0.031	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-39-040	ID 0.218	OD 0.5	Thickness 0.04	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-40-062	ID 0.234	OD 0.625	Thickness 0.062	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-41-050	ID 0.25	OD 0.5	Thickness 0.05	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-42-062	ID 0.25	OD 0.562	Thickness 0.062	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-43-010	ID 0.26	OD 0.625	Thickness 0.01	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-44-050	ID 0.26	OD 0.687	Thickness 0.05	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-45-031	ID 0.265	OD 0.5	Thickness 0.031	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-46-040	ID 0.265	OD 0.625	Thickness 0.04	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-47-050	ID 0.265	OD 0.687	Thickness 0.05	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-48-031	ID 0.265	OD 0.937	Thickness 0.031	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-49-062	ID 0.281	OD 0.5	Thickness 0.062	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity
910-50-062	ID 0.281	OD 0.625	Thickness 0.062	Material Monel	ID TOL +-.005	OD TOL +-.005	Quantity

Monel Flat Washer Frequently Asked Questions

Below are answers to some of the most common questions about Monel flat washers.

What are Monel flat washers?
Monel flat washers are manufactured from Monel, a family of nickel-copper alloys most commonly Monel 400 (approximately 67% nickel, 23% copper). Monel offers exceptional corrosion resistance in seawater, hydrofluoric acid, and a wide range of chemical environments, making Monel washers the preferred choice for marine, chemical processing, and offshore oil and gas applications.

What makes Monel washers better than stainless steel in marine applications?
Monel 400 has superior resistance to seawater corrosion and biofouling compared to 304 and 316 stainless steel. It is also resistant to chloride-induced stress corrosion cracking, which can be a failure mode for stainless steel in marine environments. For critical seawater immersion applications, Monel is the material of choice.

Are Monel washers DFARS specialty metals?
Yes. Monel and other nickel alloys are classified as DFARS specialty metals. All Monel materials used in our washers are sourced from the United States or qualifying countries in compliance with DFARS requirements. Material certifications and DFARS documentation are available upon request.

Can you make custom Monel flat washers?
Yes. Superior Washer manufactures custom Monel washers to your OD, ID, and thickness specifications. Contact us via the Quick Quote form or by phone.

Are your Monel flat washers made in the USA?
Yes. All Monel flat washers are manufactured in the United States under our ISO 9001:2015 certified Quality Management System. Material certifications are available upon request.

For applications outside seawater and chemical processing environments, we offer many other metal and non-metal materials. Browse the full flat washers catalog to explore what fits your needs.