Welcome to a closer look at Lam Cos Steel
Here we delve into the unique properties and applications of this remarkable material. Developed with precision engineering and cutting-edge technology, Lam Cos Steel offers a myriad of benefits that make it an excellent choice for a wide range of industries including knives.
With its superior strength and durability, Lam Cos Steel stands out as a reliable and long-lasting option, ideal for applications that require robustness and resistance to wear and tear. Whether it’s for construction projects, automotive components, knives, or even surgical instruments, Lam Cos Steel’s exceptional performance ensures reliability in even the most demanding environments.
In addition to its physical properties, the versatility of Lam Cos Steel shines in its ability to be easily fabricated and molded into various shapes and sizes. This makes it a favorite among designers and engineers who appreciate its flexibility and limitless design potential.
What is CoS Steel?
The alloy composition of CoS steel is fairly similar to that of AISI grade 440C steel only that it contains additional elements like Cobalt, Molybdenum, and a small percentage of Vanadium.
CoS special steel is conventionally produced and does not follow the new powder metallurgy production process of most modern steels.
The conventional production method enables the steel to be relatively affordable over the premium powder metallurgy steels like Crucibles industries powder steels.
What is Lam CoS Steel?
420J2 stainless steel offers low hardness but relatively high toughness. Lam CoS steel is commonly used in Fallkniven knives (F1, F1 pro) and some Spyderco knives.
The outstanding strength is achieved from the lamination, and good edge retention from the core CoS steel makes Lam CoS steel the perfect steel for survival and outdoor knives. What’s more, it is stainless steel; therefore, it can withstand humid and corrosive environments, unlike most tough knife steels that aren’t stainless.
Composition of CoS Steel (CoS Steel Chart)
- Carbon C 1.05%: Increases edge retention, hardness, and tensile strength. It also improves steel resistance to wear, abrasion, and corrosion.
- Chromium Cr 16.00%: Chromium Increases the hardness, tensile strength and toughness of the blade by forming chromium carbide. The higher than 13% Cr is what makes CoS steel “stainless”
- Molybdenum Mo 1.50%: It improves machinability and hardening property.
- Vanadium V 0.25%: Increase wear resistance and toughness, it also improves corrosion resistance.
- Cobalt Co 1.50% Improves the hardness of the blade as it increases the martensitic transformation temperature of the alloy, It also increases the corrosion resistance of steel.
- Tungsten W 0.25%: Increases strength of steel
Properties of CoS steel
CoS Steel Hardness
CoS steel has a hardness of 60 HRC as per the Rockwell hardness scale but it can achieve a hardness of up to 62HRC. The hardness of any steel is important because it determines the wear resistance and edge retention of steel, which are major properties in the definition of good blade steel.
With a hardness of 60 HRC, CoS steel is categorized as hard steel; therefore, we can expect good edge retention and wear resistance. The hardness differs from the manufacturer’s heat treatment. The high hardness of CoS steel is attributed to the high carbon content of more than 1% in its composition.
CoS Steel Edge Retention
The edge retention of steel is directly related to its hardness, and therefore, CoS steel offers excellent edge retention as it is a hard steel. The perfect blend of carbon, chromium, cobalt, and molybdenum contributes to its great edge retention.
CoS stainless steel edge retention is slightly better than most stainless steel and is highly similar to CPM S35VN steel and slightly better than VG10 steel.
CoS Steel Toughness
Toughness is the ability of steel to withstand impact and force from tough applications without chipping and cracking. As a rule of thumb, the higher the hardness, the less the toughness.
CoS special steel on its own offers moderate toughness slightly better than 440C stainless steel and VG10 stainless steel but lower than Sandvik 14C28N steel or Nitro V steel.
Lam CoS steel offers improved toughness over CoS steel due to the presence of tough 420J2 steel layers on the outer part of the steel. When used for tough applications, the laminate layers absorb the impact; therefore, the knife does not break or chip.
The toughness of CoS steel makes it a good choice for the manufacture of survival and outdoor knives.
- Heavy duty utility blade for general cutting, trimming, and scraping of a variety of materials
- Precision-honed edge for consistent and long cutting life
- Fits most standard utility knives
- 100 pack
- Notice: Be sure to watch our HOW-TO video before using it. It can help you slide the utility blade out quickly and easily
- Super Versatility: It is made entirely according to standard utility knife blades and fits most standard & fixed utility knives perfectly
- Affordable: Includes 100-pack replacement blades and they come in a well-built case for safe storage and disposal. Each blade is rigorously tested and we firmly believe this is a great deal
- Durability: WORKPRO utility knife blades are made from SK5 steel, which is of high quality and durability
- Sharp: The knife blades are highly sharp and cut through lots of materials easily and without hesitation. Ideal for cutting cardboard, leather, linoleum, rope, soft metal, etc
- SK5 Steel Durability: Made from industrial-grade SK5 high carbon steel, these heavy duty utility blades provide exceptional hardness and edge retention. Compared to standard carbon steel, SK5 offers improved wear resistance and extended life span, ensuring fewer blade changes and higher efficiency during cutting tasks. Whether you're working on renovation projects, packaging, or construction sites, these blades can handle tough materials like carpet, drywall, rubber, and rope with ease
- Standard Size Fit: This utility knife blades 100 pack is crafted to meet universal blade specifications, ensuring a perfect fit with most retractable utility knives, folding knives, and box cutters. Whether you're replacing utility knife blades for everyday tasks or switching out box cutter blades on the job, these standard-size blades deliver reliable compatibility and performance you can count on across various tools and scenarios
- Razor Sharp Edge: Our razor blades for utility knife are precision-honed to deliver ultra-sharp, clean cuts every time. Engineered with a refined edge angle, these blades slice effortlessly through thick cardboard, leather, carpet, vinyl, linoleum, soft metals, and more. The sharpness reduces drag, improves control, and minimizes hand fatigue—making it the ideal choice for DIYers, contractors, or warehouse professionals
- Safe Storage Box: Each set comes with a compact and durable utility blade storage box that protects blades from dust, moisture, and accidental contact. The slide-out design allows safe, one-at-a-time access to blades while keeping unused blades neatly organized. Whether stored in a toolbox, desk drawer, or tool belt, this box keeps your workspace safer and your workflow smoother
- Trusted by Pros & DIYers: These replacement blades for utility knife are built with Jetmore’s commitment to precision and durability. Whether you're a professional in construction, a warehouse operator, a DIY hobbyist, or simply handling everyday home repairs, Jetmore delivers blades you can trust. We stand behind our quality—so you can cut with confidence, knowing your tools won’t let you down
CoS Steel Corrosion resistance
What sets Lam Cos Steel apart from other materials is its exceptional corrosion resistance. Thanks to its composition and specialized treatment, Lam Cos Steel maintains its integrity, even when exposed to harsh chemicals or extreme weather conditions. This makes it a highly sought-after choice for outdoor applications, where longevity and protection against corrosion are paramount.
The chromium composition in steel determines the corrosion resistance, and it is another area of interest for many knife users. So, does CoS steel rust? No, CoS steel doesn’t rust easily as it contains 16% chromium which is enough to make it stainless steel.
Lam Cos steel is laminated with 420J2 steel with excellent corrosion resistance features. Therefore, you can take home knives made from Lam CoS steel with the confidence that they will not rust on exposure to humidity, salty water, and other corrosive environments.
While CoS steel and Lam CoS steel blade can fight corrosion, they can still rust when neglected and exposed to extremely corrosive environments. This calls for regular care. Depending on the application area, strive to wash and dry the knives after every use to keep rust and stains at bay.
CoS Steel Wear Resistance
The wear resistance of steel determines its response to wear and abrasion with continued use and sharpening. The higher the hardness of steel, the better its wear resistance. Being hard steel, CoS steel offers great wear resistance, and therefore it will serve you for a long time.
Ease of sharpening CoS steel.
The ease or difficulty of getting a sharp edge with blade steel is another major consideration for knives. The composition of Cos steel makes it very easy to sharpen. To make it even easier, we recently wrote the ultimate guide to sharpening knives with any steel.
Ease of sharpening and great edge retention make CoS stainless steel very easy to maintain steel, particularly for survival and outdoor knives.
CoS steel vs. other steels
CoS steel vs VG10
The main difference between CoS steel and VG10 Steel is that CoS steel has double the amount of Cobalt and slightly increased alloying elements over VG10 steel.
CoS steel can be viewed as an upgraded version of VG10 stainless steel. It beats VG10 steel performance in terms of edge retention, toughness, and corrosion resistance making it better in overall performance.
Lam CoS steel offers further improved performance in terms of toughness and corrosion resistance. The 420J2 steel laminate increases the toughness and corrosion resistance of Lam CoS over VG10 steel.
This is in addition to the better edge retention found in CoS steel over VG10 steel. In general, Lam CoS steel knife will outperform VG10 steel knife in all performance aspects.
CoS steel vs CPM 3V
The main difference between CPM 3V steel and CoS steel is that CPM 3V is a high-end powder metallurgy steel while CoS steel is a conventionally produced steel.
CPM 3V powder metallurgy production process enables it to achieve outstanding toughness, it thus beats CoS steel in toughness by a big margin offering almost twice the toughness of CoS steel.
Another major difference between CoS steel and CPM 3V steel is that CoS steel is stainless steel with about 16% chromium elements in its alloy composition, CPM 3V is non-stainless steel with about 7.5% chromium elements in its alloy composition. Thus CoS steel blades will offer better corrosion and rust resistance over CPM 3V blades.
CoS steel blades provide slightly better edge retention over CPM 3V blades despite having slightly lower Rockwell hardness than CPM 3V.
The slightly better edge retention of CoS stainless steel over CPM 3V can be attributed to the increased Carbon content in its alloy thus enabling a higher percentage of carbides which are great in edge retention and wear resistance.
Lam CoS steel offers enhanced toughness over CoS steel but this is not enough to beat the toughness of CPM 3V blade steel. Lam CoS steel blade will also offer better corrosion and rust resistance over CPM 3V steel blades due to the added 420J2 steels.
- 【15 Pieces Multipurpose Knife Set】 15 pieces knife set includes: 8" Chef knife, 8" Slicing knife, 7" Santoku knife, 8" Serrated bread knife, 5" Utility knife, 3.5" Paring knife, 6 Pcs 4.5" serrated steak knife, 1 Pc kitchen shear, and Black hard wood Knife Block with built-in Knife Sharpener.
- 【Black Non-Stick & Anti-Rust Coating】 The black coating on the stainless steel surface does a good job of stopping the knives from oxidizing in contact with oxygen in the air, so the kitchen knife set will remain non-stick and rust-proof for years to come.
- 【Amazing Built-in Knife Sharpener】 Kitchen knife sets with built-in sharpeners are very convenient and you can sharpen your knives with one hand. It saves you the trouble of finding a sharpener and sharpening your knives on a whetstone, which is great invention.
- 【Dishwasher Safe Sharp Knife Set】 Forged from 1.4116 high-carbon German stainless steel, this kitchen knife set is extremely resistant to stains and rust. Industry-leading tapered edge grinding technology provides optimal sharpness for precise cutting and easy resharpening.
- 【Astercook lifetime warranty system】Astercook each set of knives based on excellent quality, after strict quality inspection, superior customer service for each customer to provide a lifetime warranty, please feel free to buy!
- 【AESTHETIC KITCHEN UPGRADE】 Warm wood grain handles and a sleek black knife block make this set a countertop centerpiece — a seamless blend of modern style and everyday function that elevates any kitchen aesthetic.
- 【SMARTER 4-HOLE KNIFE BLOCK】 Unlike traditional wooden blocks that trap moisture and emit unpleasant odors, our square block features a 4-hole drainage design for rapid drying. A non-slip base keeps it firmly in place while saving valuable counter space.
- 【SHARP & RUST-RESISTANT】 Each blade is crafted from high carbon stainless steel with advanced OPD non-stick coating — food releases cleanly, rust stays away, and cleanup takes seconds. Fully dishwasher safe for easy maintenance after every meal.
- 【EFFORTLESS PRECISION CUTTING】 Engineered with a 0.618 blade ratio for a perfectly balanced cut — smooth on the push, effortless on the pull. The ergonomic handle fits naturally in your hand, reducing wrist fatigue for confident control through every slice and chop.
- 【PERFECT FOR GIFTING】 Practical enough for everyday use, elegant enough for any occasion — a thoughtful housewarming, wedding, or apartment essential for anyone who loves to cook. Arrives ready to impress, no wrapping needed.
- 14-piece knife set incluedes: (1) 8'' Chef's knife, (1) 8'' Slicing knife, (1) 8'' Bread knife, (1) 5.5'' Utility knife, (1) 3.5'' paring knife, (6) 4.5'' steak knife, (1) 8'' kitchen scissors, (1) 8''sharpener, (1) knife block
- High carbon stainless-steel blades for precision results and lasting sharpness
- Traditional, full tang, triple-riveted ergonomic knife handles offer pleasant weight for better balance and control
- For best results, wash knives by hand and dry immediately; wipe the block with a damp cloth and air-dry upside down at least once per month