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Showing posts with the label high speed steel

WHAT IS TURNED, GROUND AND POLISHED?

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Metal shafts used in high-speed applications require a large amount of precision. If the shafts have rough finishes or lack concentricity and straightness, premature wearing of either the shaft or bearing being used can occur. In order to achieve the high level of precision required, steel shaft manufacturers often use a process called turned, ground and polished. This process involves – as the name implies – three important steps that converts a coarse, roughly dimensioned metal rod to a shaft with a straight and smooth finish. Turned: First, oversized steel rods are placed into a lathe chuck and tightened, and a cutting tool is placed in the tool holder on the lathe. The lathe is then started and the rod begins to spin. Once the steel rod reaches the desired speed, the cutting tool is fed into the rod which begins the process. The turning continues until the steel rod is brought down to the desired size. Multiple passes may have to be made with the cutting tool depending on h...

7 THINGS TO CONSIDER WHEN CHOOSING AN ALLOY STEEL GRADE

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Alloy steel can be used in a wide variety of applications because there are so many different combinations of alloying elements that achieve different properties. With such a wide variety of alloying elements and combinations, choosing an alloy steel grade can be difficult. This article will explain some considerations when choosing an alloy steel for your next project. 7 things you should consider when choosing an alloy steel grade include: Does it need to have good formability? Does it need to be welded? Does it need to be machined? Does it need to have corrosion resistance? Does it need to be heat treated? What strengths are required? What are the typical applications? Does the alloy steel need to have good formability? Some elements, such as chromium and boron, increase the steel’s hardenability. Since most alloy steels are able to be hardened, forming is typically done in the annealed state of the material. Alloy steels that are annealed and have lower amou...

Hot Work Tool Steel VS Cold Work Tool Steel

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What is Cold Work Tool Steel? & What is Hot Work Tool Steel? Cold Work Tool Steel Cold work tool steel basically is high carbon steel, the alloy content contains tungsten, manganese, chromium and molybdenum relatively low alloy steel. These alloys added to improve hardenability, allowing less distortion than the W series of quenching oil. These are relatively cheap steel, high carbon content they will produce sufficient wear resistance, used for short-term operation. It is used for all types of blanking and forming dies, gauges, fixtures, etc. In ASTM Steel standard Cold Work Tool Steel main include the “W” (Water Hardening), “O”(Oil Hardening), “A” (Medium Alloy Air Hardening), “D” (High Carbon, High Chromium) Tool Steel Series. Typical Steel Grade like: W1, W2, W5 tool Steel; O1, O2, O6, O7 Oil Steel; A2, A4, A6,A7,A8, A9,A10, A11 Cold work Steel; D2,D3, D4,D5,D7 Steel; etc. Hot Work Tool Steel Hot working tool steel to make iron and nonferrous metals as well as hot for...

Good Tooling Design, Better Productivity

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There are no shortcuts in producing good tooling. Lack of attention in any of the following areas can result in poor tool quality, poor part quality, low yield or worse – tool failure: Tooling design Material selection Tooling manufacturing process Heat treating and finishing Today, we are going to talk about tooling design. Careful consideration should always be given to the design, material and fabrication of tooling – let’s face it, finished parts are only as good as the tooling used to create them. There are several variables such as heat, pressure and speed that can contribute to excessive tool wear or tool failure. Managing these variables, sourcing the right tool steel and applying good tool design sensibility will help you avoid downtime and extend tool life.  Here are some common problems and solutions to consider when designing and fabricating tooling: At Otai Special Steel we work closely with customers to help them select the right tool steel for the...

Heat Treating of Tool Steels – Annealing

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ANNEALING ANNEALING IS AN ASPECT OF HEAT TREATMENT USED TO SOFTEN STEELS AND TO IMPROVE MACHINABILITY, MATERIAL STABILITY & MECHANICAL OR ELECTRICAL PROPERTIES. THIS IS ACCOMPLISHED BY BRINGING THE STEEL TO A SPECIFIED TEMPERATURE ABOVE THE UPPER CRITICAL TEMPERATURE AND HOLDING AT THAT TEMPERATURE FOR A SPECIFIC AMOUNT OF TIME ACCORDING TO THE INSTRUCTIONS FOR THAT GRADE. ALL TOOL STEELS ARE SPHEROIDIZED ANNEALED (SPHEROIDAL OR GLOBULAR MICROSTRUCTURE) WHICH PRODUCES A FINE GRAIN STRUCTURE. THE FINE GRAIN STRUCTURE ACHIEVED THROUGH THIS ANNEALING PROCESS ALLOWS TOOL STEELS TO EXPERIENCE FORECASTED GROWTH DURING HEAT TREAT. THIS EXPECTED GROWTH IS CRITICAL TO TOOL MAKERS PRODUCING TOOLS AND PARTS OUT OF TOOL STEEL. TOOL STEELS ARE ANNEALED AT THE MILL DURING INITIAL PRODUCTION TO DIFFERENT BRINELL HARDNESS RANGES (BHN) DEPENDING ON THE SPECIFIC GRADE OF TOOL STEEL; FOR INSTANCE, AN O1 TOOL STEEL WILL BE NEAR 201 BHN IN THE AS-SHIPPED CONDITION, A SUPER HIGH SPEED GRADE SUCH...

Elements in Tool Steel

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In this article, we would like to discuss the elements that make up tool & high speed steels. What do these elements do to provide the mechanical and physical properties we need for our applications? The most common elements are the following: CARBON (C): this is the most basic alloying element which enables steel to harden. Carbon combines with the other elements to form hard, wear-resistant carbides. MANGANESE (Mn): controls hardenability in alloy cold work steels. SILICON (Si): improves toughness in the shock resisting steels group. Added to hot work steels to raise critical points and reduce scaling tendencies. Added to O-6 & A-10 to form graphite. CHROMIUM (Cr): controls hardenability and is added for abrasion resistance and hot hardness. TUNGSTEN (W): provides red hardness and hard wear resistant carbides that are harder than chrome and iron carbides. Also used to improve hardenability in tool & high speed steels. Combines very well with molybdenu...

What is the raw material of the cutting tool?

Basic properties that cutting must posses are: Tool material must be at least 30 to 50% harder than the work piece material. Tool material must have high hot hardness temperature. High toughness High wear resistance High thermal conductivity Lower  coefficient of friction Easiness in fabrication and cheap Different elements used in cutting tool materials and their properties are Element Properties Tungsten Increases hot hardness Hard carbides formed Abrasion resistance Molybdenum Increases hot hardness Hard carbides formed Improving resistance Chromium Depth hardenability during heat treat hard carbides are formed improving abrasion resistance some corrosion resistance Vanadium combines with carbon for wear resistance retards grain growth for better toughness Cobalt Increases hot hardness, toughness Carbon Hardening element forms carbides Different cutting tool materials used for cutting operations in practice are high carbon steel, high speed steel, non -f...