{"id":5911,"date":"2024-11-17T19:48:18","date_gmt":"2024-11-18T03:48:18","guid":{"rendered":"https:\/\/richconn.com\/?p=5911"},"modified":"2024-11-17T19:48:19","modified_gmt":"2024-11-18T03:48:19","slug":"tool-steel-vs-stainless-steel","status":"publish","type":"post","link":"https:\/\/richconn.com\/tool-steel-vs-stainless-steel\/","title":{"rendered":"Tool Steel vs Stainless Steel: A Comprehensive Comparison","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"\n

The steel family is huge with multiple alloys. Among them, you may have heard of stainless steel, an alloy widely used in construction and domestic applications. Equally popular is tool steel on the manufacturing side, especially in the machining industries.<\/p>\n\n\n\n

Now, in this article, we aim to compare these two steel types across their composition and mechanical properties. The idea is to reveal how distinct the two types are, so you can easily pick the right choice for your needs.<\/p>\n\n\n\n

What is Tool Steel?<\/h2>\n\n\n\n
\"\"<\/figure>\n\n\n\n

Tool steel is an engineered carbon alloy steel with exceptional hardness, wear resistance, and toughness. Its alloying elements tungsten, molybdenum, vanadium, and chromium, form carbides<\/strong>. These strongly bonded structures are fully distributed through the lattice and are responsible for its hardness.Tool steel, as in its name, was primarily made for making tools and dies<\/strong>. Due to wear resistance and ability to maintain a sharp edge at higher temperatures, it finds applications in cutting tools i.e. saw blades, drill cutters, end mills, turning tools, knives, etc.<\/p>\n\n\n\n

What is Stainless Steel?<\/h2>\n\n\n\n
\"Stainless<\/figure>\n\n\n\n

Stainless steel is a steel alloy with a minimum of 10.5% chromium content<\/strong>, which entirely shapes it whole physical and chemical characteristics. Other alloying elements \u2013 like nickel, titanium, and molybdenum \u2013 are also present in certain grades of stainless steel.This steel is best known for its excellent corrosion resistance<\/strong> and aesthetic appeal<\/strong>. So, its use is widespread in everyday applications. In construction, it\u2019s common for handrails and facades. In the auto sector, it\u2019s used for exhaust parts. Due to biocompatibility, it is also used in medical equipment and implants. Cookware is another popular application.<\/p>\n\n\n\n

Tool Steel vs Stainless Steel: 6 Differences<\/h2>\n\n\n\n

The purpose of the materials overview was to give you a quick glance at the best properties of each. Since both alloys include multiple grades, our comparison will focus on the unified properties within each family \u2013 though we will try to entertain some of their popular grades in the differences.<\/p>\n\n\n\n

1. Chemical Composition<\/h3>\n\n\n\n

The chemical makeup is what defines the distinguished characteristics of each material. Tool steels have vanadium, nickel, molybdenum, and tungsten as alloys. But it\u2019s not these elements but their ability to form carbide structure throughout the material<\/strong>. These carbides are extremely hard and improve the wear resistance, cutting ability, and longevity of tools.<\/p>\n\n\n\n

Although stainless does have multiple alloying elements the key element is chromium \u2013 at least 10.5% Cr is present in this class of metals. The chromium forms a passive oxide layer on the surface. This layer acts as a shield against corrosion, regenerating itself when damaged.  <\/p>\n\n\n\n

Unlike tool steel, carbide formation<\/strong> in stainless steel is minimal<\/strong>. However, due to the high carbon content in some stainless steels, chromium carbide precipitation can occur at grain boundaries. This phenomenon is called sensitization. This is why low-carbon stainless steel grades (e.g., 304L) are preferred in environments requiring durability against rust.<\/p>\n\n\n\n

Here\u2019s a detailed breakdown of the chemical makeup of stainless steel and tool steel:<\/p>\n\n\n\n

<\/th>Tool Steel<\/strong>
(%)<\/strong><\/th>		Stainless Steel<\/strong>
(%)<\/th><\/tr><\/thead>
Carbon (C)<\/td>0.5 – 1.5<\/td>< 0.08 (Most grades)<\/td><\/tr>
Chromium (Cr)<\/td>Normally up to 5
(Some grades higher, ~12<\/td>		10.5 \u2013 29<\/td><\/tr>
Vanadium (V)<\/td>0.1 \u2013 2<\/td>Rarely present<\/td><\/tr>
Molybdenum (Mo)<\/td>Up to 10<\/td>0 – 5<\/td><\/tr>
Nickel (Ni)<\/td>Absent or minimal<\/td>8 – 10<\/td><\/tr>
Tungsten (W)<\/td>Up to 18<\/td>Not commonly included<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

2. Manufacturing Process<\/h3>\n\n\n\n

Tool steel is made with controlled methods to optimize its hardness, toughness, and wear resistance. Here\u2019s the process journey:<\/p>\n\n\n\n

    \n
  1. The raw materials or scrap gets into an Electric Arc Furnace (EAF) which controls the chemical mix-up.<\/li>\n\n\n\n
  2. Ladle refining is carried out for the removal of impurities.\u00a0<\/li>\n\n\n\n
  3. The molten steel is either ingot cast or continuously cast into semi-finished forms like billets or slabs.\u00a0<\/li>\n\n\n\n
  4. The steel undergoes hot rolling or forging to achieve the desired dimensions and grain structure.<\/li>\n\n\n\n
  5. Heat treatment processes (annealing, quenching, and tempering) may be carried out.<\/li>\n<\/ol>\n\n\n\n

    Stainless steel production focuses on achieving superior corrosion resistance and durability.<\/p>\n\n\n\n

      \n
    1. The process starts with melting stainless steel scrap or raw materials in an EAF.\u00a0<\/li>\n\n\n\n
    2. Argon Oxygen Decarburization (AOD) refining follows, where oxygen and argon gases are injected to reduce carbon content and refine the alloy.\u00a0<\/li>\n\n\n\n
    3. Steel is continuously cast into slabs, billets, or blooms. These forms undergo hot rolling to reduce thickness and are further processed through cold rolling for precise dimensioning.\u00a0<\/li>\n\n\n\n
    4. Heat treatment is carried out to relieve stress and enhance ductility. Descaling is done for surface impurities.<\/li>\n\n\n\n
    5. Passivation is applied to strengthen the protective oxide layer, enhancing corrosion resistance.<\/li>\n<\/ol>\n\n\n\n

      3. Grades and Types<\/h3>\n\n\n\n

      Tool steel and stainless steel belong to the main steel family, but they further have multiple groups and grades, based on their respective properties and composition. <\/p>\n\n\n\n

      For tool steel, the classes are primarily based on the hardening method. The table illustrates tool steel grades and their applications.<\/p>\n\n\n\n

      Tool Steel Grades<\/strong><\/th>Characteristics<\/strong><\/th>Applications<\/strong><\/th><\/tr><\/thead>
      Water-Hardening (W)<\/td>High hardness
      Lower toughness
      Inexpensive<\/td>      		Hand tools, woodworking tools<\/td><\/tr>
      Cold-Work (O, A, D)<\/td>High wear resistance
      Moderate toughness
      Used at lower operating temperatures.<\/td>      		Dies, punches, tools for cold forming.<\/td><\/tr>
      Hot-Work (H)<\/td>High thermal stability\u00a0
      Retains hardness and toughness at elevated temperatures.<\/td>      		Die-casting dies, hot forging tools, extrusion tools.<\/td><\/tr>
      High-Speed (M, T)<\/td>Retains cutting edge at high temperatures.<\/td>Cutting tools like drills, milling cutters, and taps.<\/td><\/tr>
      Shock-Resisting (S)<\/td>High impact resistance
      Moderate wear resistance<\/td>      		Hammers, chisels, shear blades, impact tools.<\/td><\/tr>
      Mold (P)<\/td>Good machinability, polishability, and toughness.<\/td>Plastic injection molds, die-casting molds.<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

      In the case of stainless steel, the classification is based on metallurgical structure, composition, and heat treatment. The class of stainless steel and their respective applications are listed in the table.<\/p>\n\n\n\n

      Stainless Steel Groups<\/strong><\/th>Characteristics<\/strong><\/th>Applications<\/strong><\/th><\/tr><\/thead>
      Austenitic<\/td>Non-magnetic
      Excellent corrosion resistance\u00a0
      Good weldability and ductility<\/td>      		Kitchen equipment, food applications.<\/td><\/tr>
      Ferritic<\/td>Magnetic
      Moderate corrosion resistance
      Good formability
      Lower cost<\/td>      		Automotive trim, appliances, decorative items.<\/td><\/tr>
      Martensitic<\/td>Magnetic
      Heat-treatable
      High strength and hardness
      Less corrosion resistance<\/td>      		Cutlery, surgical tools, bearings.<\/td><\/tr>
      Duplex<\/td>Balance of ferritic and austenitic properties.<\/td>Oil and gas, chemical processing.<\/td><\/tr>
      Precipitation-Hardening<\/td>High strength\u00a0
      Excellent corrosion resistance
      Age-hardenable<\/td>      		Aerospace, automotive, structural applications.<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

      4. Mechanical Properties<\/h3>\n\n\n\n

      The mechanical properties also differ due to their different chemical makeup. For manufacturers properties that matter most include strength, durability, and hardness. <\/p>\n\n\n\n

      We have repeatedly mentioned the tool steels outshine stainless steel in hardness (up to 70 HRC<\/strong>) and wear resistance. So, their first use case is cutting tools. They do offer great strength but their brittle nature doesn\u2019t make them great for pure structural and load-bearing applications. Another reason is their low corrosion resistance. <\/p>\n\n\n\n

      On the other hand, stainless steel brings a different set of strengths to the table. Most stainless steel grades don\u2019t match tool steel’s hardness but the hardness is slightly higher in martensitic grades (58 HRC<\/strong>). Moreover, the young\u2019s modulus and comparatively ductile nature make it suitable for load-bearing and structural applications. <\/p>\n\n\n\n

      Corrosion resistance is what truly sets the stainless steel apart, thanks to its chromium content (>10.5%). It creates a protective oxide layer which makes it rust-free and durable. The following table presents our detailed outlook of mechanical properties of the two metals:<\/p>\n\n\n\n

      <\/th>Tool Steel<\/strong><\/th>Stainless Steel<\/strong><\/th><\/tr><\/thead>
      Hardness<\/strong><\/td>High (58\u201368 HRC)<\/td>Moderate (70\u201390 HRB);
      up to 58 HRC (martensitic)<\/td><\/tr>
      Tensile Strength<\/strong><\/td>450 to 2500 MPa<\/td>515\u20131300 MPa<\/td><\/tr>
      Ductility<\/strong><\/td>Low (more brittle)<\/td>High (good ductility)<\/td><\/tr>
      Corrosion Resistance<\/strong><\/td>Poor<\/td>Excellent<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

      5. Machinability<\/h3>\n\n\n\n

      High resistance and hardness mean trouble for tools and challenges in machining but largely most of them are machinable except few grades. For instance, D2 tool steel has a machinability rating of approximately 27%, which hints that it\u2019s more difficult to machine compared to standard carbon steel. However, W1 grade is one of the easiest ones to tackle.  <\/p>\n\n\n\n

      Stainless steel is also challenging to machine, especially austenitic grades like 316. Their low thermal conductivity, ductile nature, and work hardening make them challenging. The machinability rating of grade 316 is about 36%.<\/p>\n\n\n\n

      6. Price<\/h3>\n\n\n\n

      The price of alloys is based on the alloying elements and manufacturing method. In general, the tool steel is more expensive to due the precise alloying process and expensive treatment. Whereas, stainless steel is relatively affordable and one of the reasons why it\u2019s very common in domestic. The commonly used stainless steel 304 is priced at $0.66\/lb.<\/p>\n\n\n\n

      Tool Steel vs Stainless Steel: Which One\u2019s Right for Your Project<\/h2>\n\n\n\n

      Now, it comes down to selecting the right material for your needs. We have already detailed the specific properties and grades of both tool steel and stainless steel. To further simplify the decision, let\u2019s outline scenarios where each material excels and is most favorable.<\/p>\n\n\n\n

      Choose tool steel:<\/h3>\n\n\n\n