Corrosion Coupons

Accurate monitoring of corrosion rates in any environment is critical when viewed in terms of the maintenance and repair costs associated with corrosion and material failure. Test coupons provide an inexpensive means of on-line monitoring that will allow you to effectively measure the corrosivity within your system. By observing the mils-per-year corrosion rate of an exposed coupon, valuable information can be provided regarding the material's life expectancy.

Metal Samples can make coupons in any size, shape, or material you need. Coupons can be stenciled with alloy and sequence numbers for proper identification. Mill test reports, identifying element compositions of materials used, are provided on all orders.

Coupon after being exposed to corrosive environment.

The following coupons are four of the most commonly used in corrosion testing.
Custom coupon sizes available.

P/N CO100	P/N CO131
Shape Rectangular Finish Double disc or glass bead Identification Stenciled - alloy, heat no., sequence Surface Area 3.38 in2	Shape Rectangular Finish 120 grit, glass bead, or mill Identification Stenciled - alloy, heat no., sequence Surface Area 3.47 in2

P/N CO146	P/N CO220
Shape Rectangular Finish Glass bead or mill Identification Stenciled - alloy, heat no., sequence Surface Area 4.26 in2	Shape Circular Finish 120 grit, glass bead, or mill Identification Stenciled - alloy, heat no., sequence Surface Area 2.72 in2

Flat Coupons

The coupons listed above can be made from a variety of materials (see Alloys list).

Cylindrical Coupons

* ES209 has five 1/8" diameter scale holes.

Scale Coupons

Scale coupons (or deposition coupons) provide a qualitative measure of relative deposition rates in industrial water and manufacturing process systems.

	P/N CO115 - flat coupon
	P/N ES209 - cylindrical coupon

Finishes

Coupons can be furnished with a variety of finishes depending on your particular application. Some of the typical finishes available are defined below.

• Mill - finish as produced from mill.
• Glass Bead - blasted with fine glass beads to remove mill scale.
• 120 Grit - fine finish using a 120 grit belt and commonly used in corrosion tests, such as pitting studies, where smooth surface finish is desired. Finishes up to 600 grit (extremely fine) can be provided by using belt sanders.
• Double Disc Ground - extra fine finish using an abrasive disc that leaves minimal residue. Excellent for studies where surface finish is critical. Capable of producing 16-32 RMS finishes on common steels and 8 RMS on carbide steels.

Coupon Ordering

When placing your order for test coupons, please be ready to provide the sales person with information regarding the type of material you are testing, the size of the coupons you require, surface finish desired, and if applicable, mounting hole size and location.

Welded Coupons Welded coupons are used to study the variance in corrosion rates between welded and non-welded metals.			Stressed Coupons These coupons are used to monitor stress corrosion cracking which occurs when stress combines with a corrosive environment to attack a material.
Test Racks We offer test racks for the mounting of coupons of various alloys to evaluate how corrosion would effect differing materials in your system.			Coupon Holders We carry a variety of pipe plug coupon holders (for flat and round specimens), retractable coupon holders (hand insertable types for low pressure rating systems and packing gland types for ratings up to 1,500 psi.), and retrievable coupon holders (for up to 3,600 psi.).
Technical Information on Coupon Testing This article provides general requirements for coupon tests, types of coupon tests, advantages of coupon testing, and other helpful information.			Bypass Piping Systems Metal Samples provides bypass piping systems for on-line corrosion monitoring. More.
Alloys Available for Coupons			Alloys Listed by Trademark