D2 steel has been around for a long time with its related information ranging from the early 20th century. During world war, II D2 steel was heavily used to punch out steel parts for vehicles and airplanes. It was designed to punch multiple parts repeatedly an attestment to its hardness and excellent edge retention.
What is D2 Steel?
D2 steel is a die type of steel, evidenced from the letter D in its name. D2 is an air-hardening, high carbon steel, high chromium steel. It has one of the highest levels of carbon among tool steel alloy.
However, D2 steel is not categorized as stainless steel because it has a chromium composition of 11.5 to 12%, which does not meet the 13% chromium content to make it stainless. Because of this, D2 tool steel is referred to as semi-stainless tool steel.
In addition, this steel belongs to the cold-work category of steel because it is shaped after cooling, usually at the ambient temperature.
D2 tool steel also experiences low distortion and has better machining quality compared to other high chromium steel due to its carbide forming elements.
D2 is made following the air quenching process, giving it the ability to achieve and retain its hardness at different temperatures.
D2 steel Chemical composition
- Carbon C 1.50%: Increases the edge retention, hardness and tensile strength. It also improves steel resistance to wear, abrasion and corrosion.
- Chromium Cr 12.0%: Chromium Increases hardness, tensile strength and corrosion resistance of the steel.
- Molybdenum Mo 0.80%: It improves machinability and gives D2 steel the characteristic air hardening property.
- Vanadium V 1.10%: Increase wear resistance and toughness, it also improves corrosion resistance. Vanadium acts by improving the grain structure and the carbide structure of the steel.
- Manganese Mn 0.45%: improves the strength and hardness of steel. When the steel is heat-treated, hardenability is improved with increased manganese.
- Silicon Si 0.40%: Increases strength and heat resistance.
- Phosphorus P 0.03%: Improves machinability and hardness.
- Sulfur S 0.03%: Improves machinability.
Properties of D2 steel
D2 composition determines its properties; these include:
D2 steel hardness
According to the Rockwell C hardness scale, D2 has a Rockwell hardness of 60 HRC. The hardness may however vary with the tempering temperature. With such hardness, a blade made from this steel can hold edges for a long time in addition to admirable wear resistance.
D2 Wear resistance
D2 steel is known for its excellent wear resistance. If you ask around knife users, they will tell you that D2 takes the crown in wear resistance.
This feature is attributed to the good mix of chromium, carbon, vanadium, and manganese in its composition. This property makes the D2 steel knife the best for abrasive cutting compared to other types of steel on the market.
D2 steel Edge retention
As always, steel with high hardness makes blades with good edge retention, which is true with D2 steel. According to Bohler Udderholm, the edge retention of D2 is better than that of 154CM, grade 440C and it is similar to that of CPM 3V steel but significantly worse than that of S35VN, S30V, and M390 steels.
The high carbon levels in its composition make this possible. If you are on the market for a knife that will not require frequent sharpening, look into the options made from D2 steel.
D2 Steel Toughness
You cannot get hardness and toughness from the same steel, and this is the case with D2. Since it has high hardness, its toughness scores low. While there are steels with better toughness than D2, it offers enough hardness to handle light chopping without breaking.
However, consider tougher steels like X50CrMoV15 if you are looking for a knife to handle tough applications like batoning and chopping.
D2 Steel Sharpening
Sharpening D2 steel is a challenging task considering that it is hard steel and high on abrasion and wear resistance. It will take you more effort and time to achieve an ultra-sharp edge with D2, but this is compensated with long edge retention, reducing the frequency of sharpening.
Inexperienced knife sharpeners struggle to get an edge from D2 steel knives, but it is doable, especially using diamond or ceramic sharpeners on the blade.
D2 Steel Corrosion resistance
The fact that D2 is not stainless steel discourages many people from buying it because of the assumption that it rusts. To clear the air, let us answer a very common question, does D2 steel blade rust? The honest answer will be yes; it does rust but not as easy as many knife users assume.
While it does not contain the required chromium levels to make it stainless steel, its 12% chromium content is enough to resist corrosion with good care and maintenance.
You cannot keep your D2 steel knives dirty and wet and expect them not to rust, it requires regular clean-up after use.
D2 Steel comparison
D2 vs S30V
S30v blade is made from premium steel; hence it is more costly than D2 blade. In addition, it is better in corrosion resistance, edge retention, and it’s easy to sharpen. They exhibit the same level of toughness.
D2 vs 8Cr13MoV
8Cr13MoV is a high chromium Chinese stainless steel, unlike D2 which does not have enough chromium to make it stainless steel. The Cr percentage gives 8cr13mov blade better corrosion resistance and ease of sharpening.
D2 tool steel beats its counterpart in edge retention and wear resistance.
CPM D2 vs D2
CPM-D2 is a powder metallurgical variant of the D2 steel. It is a relatively new steel blade in the market following advancement in steel production by Crucible CPM technology.
It is more refined and has reduced chromium carbide required in die steels. It also provides a better toughness value than regular D2 steel and responds better in heat treatment.
Is D2 knife steel good?
The high wear resistance and edge retention make D2 blade a perfect choice for knives. You might struggle a bit with sharpening, but D2 knives are quality and affordable options.
It is suitable blade steel for a seasoned knife maker and user alike. Reputable Knifemakers like Bob Dozier have solely built their name in knife blades by utilizing D2 steel.
If you were struggling to decide on whether or not to buy a D2 steel knife, this review should give you the go-ahead. A blade from D2 is a good option compared to other non-stainless steels on the market.
D2 steel is conventionally produced and thus widely available from most tool steel companies, this makes it cheaper and easier to find as compared to powder steel. You can also find D2 as Bohler K110 Steel