What is AUS 8 steel?
AUS 8 steel is a budget Japanese-made stainless steel belonging to the AUS series lineup, consisting of AUS 4, AUS 6, AUS 8, and AUS 10. Aus-8 steel is sometimes referred to as AUS 8A or simply 8A.
Its performance is comparable to other blade steels like AISI 440B and the popular Chinese-made 8Cr13MoV stainless steel. Aus 8 stainless steel is produced by AICHI steel company.
Knifemakers highly favor it as it provides excellent balance in edge retention, corrosion resistance, and price. It is an easy steel to work on, and with good heat treatment, it can get up to the 60HRC mark.
AUS 8 Steel Composition
|Carbon C||0.70%-0.75%||Increases edge retention, hardness, and tensile strength. It also improves steel resistance to wear, abrasion, and corrosion.|
|Chromium Cr||13.00%-14.50%||The formation of Chromium carbide Increases the hardness, tensile strength, and corrosion resistance of the blade.|
|Nickel Ni||0.49%||Adds Toughness to the blade, it also improves the corrosion resistance and oxidation at elevated temperatures|
|Vanadium V||0.10%-0.26%||Forms hard vanadium carbide in combination with other elements that improve wear resistance.|
|Molybdenum||0.10%-0.30%||It improves machinability, hardness and corrosion resistance in steel.|
|Manganese Mn||0.50%||Improves the strength and hardness of steel. When the steel is heat-treated, hardenability is improved with increased manganese.|
|Silicon Si||1.00%||Increases strength and heat resistance.|
|Sulfur S||0.03%||Improves machinability but is regarded as an impurity in high quantities.|
|Phosphorus P||0.04%||Improves machinability and hardness, but is regarded as an impurity in high quantities.|
AUS 8 Steel Properties
AUS 8 Steel Hardness
AUS-8 steel has a Rockwell hardness of 58-59 HRC. The hardness of AUS 8 is highly dependent on the heat treatment technique. It is capable of achieving 60HRC with good heat treatment.
Benchmade knife company has proven consistently that their heat-treated AUS 8 steel blades can achieve 59- 60 HRC. This makes their AUS-8 stainless steel knives a very suitable budget offering.
AUS 8 Steel Edge Retention
Edge retention of AUS 8 steel is directly affected by the hardness. The higher the Rockwell hardness achieved in heat treatment, the better the edge retention of the steel. At a hardness of about 59 HRC, AUS 8 stainless steel edge retention is considered good, above average.
Its edge retention is similar to its Chinese copy 8Cr13MoV stainless steel and the popular highly stainless Spyderco salt series LC200N steel. It offers better edge retention than most low carbon alloys as it contains a bit of vanadium that enables the formation of hard vanadium carbides that are excellent.
Ease of sharpening AUS 8 Steel
In addition to edge retention, AUS 8 steel knives are easy to sharpen. A standard aluminum oxide abrasive sharpening tool can quickly give you an impressive edge that will last for a long.
AUS 8 Steel Wear resistance
AUS 8 stainless steel contains a high amount of carbon and molybdenum in its composition, making it good in wear resistance. Irrespective of the usage, knives made from AUS-8 steel remain in good shape for a long time unless subject to constant aggressive sharpening.
AUS 8 Steel Corrosion Resistance
AUS 8 steel contains high levels of Chromium (up to 14.50%), which qualifies it as stainless steel. It also includes other elements in its alloy like Nickel, which improves its corrosion resistance, ranking it among the top budget steels with high corrosion resistance.
AUS-8 stainless steel blade steel corrosion resistance is good, similar to that of 8Cr13MoV and 154CM steel. However, this does not take the knives off the rusting hook. Proper care and maintenance are critical to protecting them from rusting, especially in high humidity areas.
Is AUS 8 steel tough?
AUS 8 steel toughness is better than most stainless steel out there. For context, AUS 8 steel toughness beats most crucible S series blade steels, including the popular S30V and S45VN. Molybdenum and Nickel in AUS 8 steel alloy significantly boost its toughness.
Knives made from this material are highly resistant to chipping, cracking, or breaking even under pressure. Its toughness is comparable to that of 26C3 Steel but is lower than the New Magnacut Steel.
AUS 8 Steel Machinability
The Sulfur and Molybdenum in this Japanese steel give it excellent machinability. Knifemakers find this type of steel easy to work with because it is easy to cut and can achieve a good finish without struggling.
Pros and cons of AUS 8 Steel
- Easy to sharpen and stays sharp for long, making it easy to use
- It has corrosion resistance features, making it safe for meal preparation
- It has decent edge retention releasing you of the burden of frequent sharpening
- It is tough; therefore, it can be used for hard cutting jobs without the fear of breaking.
- Knives made from AUS-8 steel are affordable.
- The knives become dull quick under consistent use.
- The quality of the knives depends on manufacturer adjustments during production and daily usage.
AUS 8 steel vs other steels
8cr13mov vs AUS 8
AUS 8 is slightly better than 8Cr13MoV on paper, however, in real life scenario, you can’t tell the difference. The biggest difference between them is that AUS-8 is a Japanese type of steel, while 8Cr13MoV is made in China. However, it is claimed that 8Cr13MoV was a carbon copy of AUS 8 stainless steel.
Looking at the composition of 8Cr13MoV and AUS-8 steel closely, we see that AUS-8 has a bit more Nickel elements than 8Cr13MoV which may enhance AUS-8 stainless steel property and toughness.
AUS8 and 8Cr13MoV Rockwell hardness and edge retention are similar, so is their ease of sharpening. Either way, 8Cr13MoV can be termed as AUS-8 stainless steel equivalent.
|8Cr13MoV Steel||AUS 8 Steel|
AUS8 vs 440C
440C stainless steel is a better blade steel than AUS-8 stainless steel in terms of edge retention and corrosion resistance. AISI 440C steel was regarded as a premium high carbon stainless back then but time has changed and it now is in the budget range just like AUS 8 stainless steel.
440C stainless steel offers better edge retention than AUS 8 stainless steel due to the high amount of carbon in its composition which enables it to attain 60+ Rockwell Hardness.
The high volume of carbon enables the formation of a large volume of carbides which is good for edge retention.
AISI 440C steel also offers slightly better corrosion resistance than AUS-8 due to the higher percentage of chromium elements in its alloy composition.
AUS 8 stainless steel blade offers double the toughness of 440C steel blade. The mixture of high carbon and chromium also impacts 440C steel negatively when it comes to toughness.
The formation of brittle chromium carbides greatly reduces the toughness of 440C blade steel.
|AUS 8 Steel||440C Steel|
AUS 8 vs S30V Steel
The main difference between AUS 8 Steel and CPM S30V steel is that S30V steel is often regarded as premium steel while AUS 8 steel is budget steel. S30V steel offers twice the edge retention of AUS 8 stainless Steel. It also beats Japanese AUS 8 steel in corrosion resistance.
S30V steel beats AUS 8 steel in edge retention due to several factors. First, S30V has a Rockwell hardness of about 61HRC, while AUS8 steel Rockwell hardness is about 59HRC. The increased hardness increases the edge retention of S30V over AUS8 steel.
Secondly, the production process of S30V steel allows the formation of a large number of hard vanadium carbides. The vanadium carbides significantly improve the edge retention of S30V blade steel over AUS 8 stainless steel.
S30V blade steel also offers better corrosion resistance than AUS 8 blade steel due to its alloy composition balanced to produce vanadium carbides leaving enough chromium to improve its stainless steel properties.
AUS8 stainless steel, however, beats S30V steel in toughness due to its relatively low hardness and lack of large brittle carbides. It is also easier to sharpen AUS 8 knife steel compared to sharpening an S30V blade.
|AUS 8 Steel||S30V Steel|
AUS 8 vs VG10
AUS 8 stainless steel and VG10 steel are popular Japanese stainless steels. They both have very different alloy compositions. VG10 stainless gives better performance than AUS 8 stainless steel and is always regarded as premium Japanese blade steel due to its composition being fortified by vanadium and cobalt.
VG10 stainless steel achieves a higher hardness of up to 62HRC; this, in turn, gives it better edge retention than AUS-8 stainless steel. VG10 steel edge retention is similar to Bohler N690 steel and crucible CPM 154 stainless steel.
VG10 stainless steel also offers better corrosion resistance than AUS 8 stainless steel due to the higher amount of chromium elements and the addition of Cobalt in its alloy composition. VG10 stainless steel corrosion resistance is like that of Japanese Super Gold 2.
AUS 8 stainless steel, however, beats VG10 stainless steel in toughness. AUS 8 offers excellent toughness and is suitable for knives that require demanding applications. AUS 8 Steel is also much easier to sharpen as it does not contain a huge volume of hard vanadium carbides.
|AUS 8 Steel||VG 10 Steel|
AUS 8 vs 9Cr18MoV
The main difference between AUS 8 steel and 9Cr18MoV steel is that AUS 8 steel is Japanese-made stainless steel, while 9Cr18MoV steel is Chinese-made Stainless steel. Both steel fall in the budget category, with both offering almost similar levels of Hardness at around 58 – 60 HRC.
Both blade steels achieve an almost equal amount of edge retention with this similar hardness level, particularly when sharpened to the same angle.
Both steels should not be sharpened at a too-shallow edge as they won’t hold up well. 9Cr18MoV particularly will tend to roll edge faster due to it being less tough.
Japanese AUS 8 steel is tougher steel than 9Cr18Mov steel. AUS 8 steel will be more suitable for larger, longer blades than 9Cr18MoV as it is less likely to break and chip when these two blade steels are put head to head.
9Cr18MoV stainless steel is better at corrosion resistance than AUS-8 stainless steel as it contains more chromium elements in its composition.
The ratio of carbon to chromium enables the adequate formation of carbides and some chromium left for corrosion resistance.
Having experience with both blade steels, I’d say the Chinese made 9Cr18MoV false somewhere between AUS 8 stainless steel and 440C stainless steel.
AUS 8 stainless steel is easier to sharpen and tough, while 9Cr18MoV is more corrosion resistant and may get better edge retention when sharpened at a suitable angle.
Is AUS 8 stainless steel good for knives?
AUS 8-stainless steel is good budget steel for knives. It might not match the qualities of superior steel grades, but its sharpness, edge retention, machinability, wear resistance, and corrosion resistance make it an ideal choice for knives.
Is AUS 8 steel good?
AUS 8 stainless steel features make it a good choice for knife makers. AUS 8 offers a good balance between edge retention and toughness and is good enough for long blades. Although it is corrosion-resistant, you are advised to take care of the knife, primarily if you reside in humid areas.
My name is Jonathan M, and I’m a passionate Mechanical Engineer, a knife enthusiast, and the author of this website. I have a bachelor's degree in Mechanical engineering with a specialization in material science. I am particularly interested in researching knife steel, knife properties, and brands. I hope you will find value in the articles on this website. Contact me if you have any questions or input!