Wilfley Blog

Wilfley’s WCD4™ Duplex Stainless Steel

on December 10, 2013

Wilfley has always been on the cutting edge of new metallurgical breakthroughs, including WCD4™ duplex stainless steel, the MAXALLOY® family of hard irons, and our new Alloy C Max nickel based alloy.

Wilfley’s WCD4™ duplex stainless steel is chemically identical to standard CD4MCuN (ASTM A890 Grade 1B) but has significantly improved mechanical properties and corrosion resistance. These improvements are achieved through a proprietary manufacturing process developed at Wilfley.

WCD4™ is ideal for erosion-corrosion applications due to its hardness and improved corrosion resistance. Pump wear parts made from WCD4™ are expected to have better wear life than the standard stainless steel and CD4MCuN materials. WCD4™ is available for many different Wilfley pump models, including the A7, A9, and Kpro®.

Mechanical Properties:

Material Average Hardness
Tensile Strength
Yield Strength
CD4MCuN 250 Min. 100,000 Min. 70,000 16
WCD4™ 345 Min. 150,000 Min. 112,000 16
Improvement 38% 50% 60%

Despite identical chemical composition, the WCD4™ optimized microstructure ensures significantly better mechanical properties than Standard CD4MCuN .

Average Hardness of Austenite and Ferrite:


The microstructures of Wilfley’s WCD4™ and standard CD4MCuN are significantly different. Standard CD4MCuN has large austenite grains (A) and ferrite pools that don’t contain secondary austenite (B). WCD4™ has smaller and discontinuous austenite grains (C) and ferrite pools that are loaded with secondary austenite (D). Because austenite is nobler than ferrite, the higher amount of secondary austenite increases the overall corrosion resistance.


Wilfley Centrifugal Pumps and Variable Speed

Standard CD4MCuN

Wilfley Centrifugal Pumps and Variable Speed


Wilfley has seen plenty of success with WCD4™ duplex stainless steel throughout the years. Contact your local Wilfley representative today to learn how our metallurgical advancements can give you the advantage you need.

Download the WCD4™ Material Datasheet

Mark ScottWilfley’s WCD4™ Duplex Stainless Steel