Powder metallurgy involves heating compacted metal powders just below their melting temperatures to create hardened Net Shape geometries. It is the best method for producing high-quality parts for numerous significant applications.
The popularity of powder metallurgy can be attributed to the advantages the technique has over conventional metal forming processes like forging and metal casting. These benefits include better material utilization, increased shape complexity, and improved near-net-shape dimensional control. Additionally, this method is renowned for promoting sustainability.
Powder metallurgy has several advantages over other techniques. Enhanced product quality, shape and material flexibility, application variety, and cost-effectiveness impact the part-to-part homogeneity of components produced through this method.
The Powdered Metallurgy Process
Powder metallurgy is a process that creates precise and accurate parts by applying a range of pressures to press powdered metals and alloys into a hard tooling . Here are the four fundamental processes in this technique:
All metals and alloys can be reduced to a powder, regardless of the method utilized. For instance, various techniques can be used to create non-ferrous metal powders in different applications. Meanwhile, almost all iron powders used in producing powder metallurgy structural parts are produced either by the sponge iron method or water atomization.
Aside from atomization, other procedures for creating powder include chemical reduction, electrolytic deposition, and atomization.
Mixing and Blending
To ensure the finished product has the required properties, powders are mixed and blended with other powders, binders, and lubricants. Depending on the item’s specifications, this can be wet or dry. Further, adding alloys and a pressing lubricant is usually included in this process.
Compressing the powder mixture into the required form or tooling is known as compacting. When done correctly, compacting reduces potential voids and greatly boosts the product’s density.
Each type of metal powder requires a particular compacting pressure — from 80 MPa to 1600 MPa — depending on its characteristics. For example, the pressure for compacting soft powder ranges from 100 MPa to 350 MPa, while the pressure ranges from 400 MPa to 700 MPa for harder, more resilient metals like steel and iron.
In this step, the material is heated to a temperature below the melting point of the main component, typically in a protective environment. Liquid phase sintering refers to situations where a minor constituent can occasionally form a liquid phase at the sintering temperature.
Components Manufactured Using the Powdered Metallurgy Process
Powder metallurgy may be used to meet the requirements of any application or production process, and almost all manufacturing companies use it. Among these applications includes areas in the industries below:
The capacity to generate complex configurations utilizing efficient production techniques is one of powder metallurgy’s benefits for producing vehicle parts. Finishing or machining are unnecessary if complex components can be produced without waste or scrap.
When it comes to powder metallurgy, one of the most frequently produced items is gears. This process provides outstanding precision, extending gears’ life. Champhers and various techniques can be used to localize density,increase strength and improve smoother outcomes. .Compound gears can be made net without separate gears or assemblies.
Oil and Gas Industry
Exploration for gas and oil requires hard metal and diamond-cutting equipment. Powder metallurgy creates tools from austenitic and stainless steels to fill this need.
Powdered and Sintered Parts From Allied Sinterings
Since 1959, the knowledgeable staff of Allied Sinterings has produced reliable and high-quality powdered and sintered metal goods. Our proficiency with complex and intricate geometries using top-notch powders and materials is well-known and appreciated among clients in the telecom, automotive, medical, and industrial equipment industries.
Experience world-class services from Allied Sinterings! Contact us today.
Gears are essential components in many mechanical systems, especially in transmitting power and motion from one rotating shaft to another. They come in various shapes and sizes, each with its unique set of advantages and disadvantages. Particularly, mechanical gears are utilized to increase productivity and reduce costs. Some applications include assembly lines, robots, conveyor belts, and packaging equipment.
This article will discuss the uses of gears in common manufacturing applications and custom gears used in niche industries with high-end requirements.
How Gears Work
Gears transmit torque by interlocking, facilitating the transfer of rotational force from one unit to the next. They function as a pair and are connected to a shaft or the base part of a machine. Additionally, the ratio between two interlocking gears is established by their number of teeth.
If the driving gear (input) is greater than the number of teeth on the driven gear (output), the output will rotate at a slower speed but with greater torque. Conversely, if the driving gear has few teeth, the output turns faster with less force.
Specialized Types of Gears and Their Applications
Allied Sinterings specializes in producing small, precision-made gears for various applications. These custom gears are used in multiple industries, such as Medical devices, robotics, and electric vehicles (EVs). Here are some of the most commonly used specialized components:
Electric vehicle actuator gears are mechanical components used to control the movement and positioning of different parts in an electric vehicle. They are typically precision-engineered and designed to withstand the high loads and stress in EVs.
Planetary gears are a type of gear system consisting of sun, planet, and ring gear. They are designed to provide high gear ratios in a compact space and are widely used in automobiles. Moreover, their unique design allows multiple gear ratios within a single system, making them a versatile and efficient power transmission solution.
Harmonic Drive Gears
The harmonic drive gear system is distinguished by its unique design, which enables high precision and accuracy in a compact size. This makes it a popular option for applications requiring high precision, such as robotics, semiconductor manufacturing, and aerospace.
One of its advantages is its ability to achieve a high reduction ratio in a smaller package. This is particularly beneficial for applications where space is limited. In addition, it has a high torque and a low backlash, which is the minimal amount of play or looseness between the gears.
Spur gears are characterized by their straight teeth and are the most commonly used type in medical devices. They are typically used to power surgical instruments, pumps, and other mechanical systems. In addition, their simple designs are easy to manufacture and maintain, making them an ideal choice for applications requiring reliability and durability.
Stepper Motor Gears
Stepper motor gears enhance the performance of stepper motors by improving their torque and precision. These gears are precisely manufactured to complement the control capabilities of stepper motors. They also regulate the movement of the device’s various components — such as wheels, actuators, and mechanical systems — to ensure accurate and controlled motion.
Shift Gears for Wire Systems
Shift gears for wire systems are mechanical or hydraulic components used to control the speed and torque of the wiring system output. They can also be controlled manually or automatically and are typically used with a gearbox and a brake system.
Custom Engineered Small Gears From Allied Sinterings
Allied Sinterings is an industry leader in custom-designed small gears! Our products are precisely manufactured to the highest quality standards to ensure that they meet the specific requirements of our customers. We also use advanced technology to continuously improve our products and services and provide everyone with innovative solutions to their needs.
Sintering uses pressure and heat to form powdered metal materials into a 80-95% solid mass without fully melting the metal. As the metal granules are pressed together, they begin to bond together the irregular particles to form a “green” compact. These compacts interconnected particles are then sintered to melt the particles together giving the component strength. Powdered metallurgy processes afford the ability to create small net shape parts with complex geometries while generating little waste.
Allied Sinterings, Inc. offers numerous varieties of powdered steel for creating small and miniature parts using the sintering process. This blog will highlight the two most common steel grades we utilize in this manufacturing process – stainless steel and nickel steel.
Advantages of Stainless Steel Components
A steel alloy containing more than 10.5% chromium is considered stainless steel. As one of the most widely used materials, stainless steel is a common base metal for powdered metal processes. The material offers numerous properties that make it an ideal material for producing powdered miniature components. Powdered stainless steel is available in multiple 300 series and 400 series grades.
Some of the beneficial properties of powdered stainless steel include:
Corrosion resistance. The chromium within the stainless steel alloy reacts with oxygen to create a protective film on the surface of the metal that protects against corrosive elements.
Improved strength. Stainless steel offers good strength and can support significant weight.
Durability. Stainless steel’s high corrosion resistance, excellent strength, and broad temperature range make it highly durable in an expansive range of environments.
Highly recyclable. As a 100% recyclable material, stainless steel is the most recycled material in the world. Demand remains high enough to outpace the availability of recycled materials, but about 60% of all new stainless steel is generated from recycled material.
Wide temperature range. The functional temperature range of stainless steel varies widely based on the specific alloy. Some austenitic alloys used in natural gas applications perform well in temperatures as low as -161°C. Many common grades of stainless steel will maintain their oxidation resistance under exposure to temperatures as high as 870°C, and some specialty alloys can tolerate even higher temperatures.
Sintered stainless steel serves many different types of applications. The medical industry uses powdered metallurgy to develop precision stainless steel parts for critical medical devices. Automotive and industrial equipment often incorporate small, sintered parts, such as gears, as crucial components of larger products. The growing telecom industry turns to sintered stainless steel miniature components for highly complex devices.
The Benefits of Nickel-Steel Alloys
Adding nickel to steel alloys provides a variety of benefits, including:
Good formability. The ductile nature of nickel-steel alloys makes them highly formable, which can be beneficial for powdered metals that need additional finishing or machining after the sintering process.
Improved strength/toughness. Adding nickel to a steel alloy imparts enhanced strength into the metal while improving resistance to cracking.
Good weldability. Nickel improves the weldability of steel by decreasing brittleness and improving welding bonds.
Resistance to high operating temperatures. Nickel improves the stability of the protective oxide layer in steel, which helps the layer better tolerate prolonged exposure to high temperatures.
Nickel steel and nickel stainless steel alloys see broad usage because of their versatility and availability. The pharmaceutical and chemical industries use sintered nickel alloy components within a variety of process equipment. Applications concerned with cleanliness, such as medical or food and beverage facilities, often utilize sintered nickel steel alloy components for their hygienic properties. The aerospace industry prefers nickel alloys for miniature parts for their high strength and ability to operate in a wide temperature range.
Custom Miniature Parts from Allied Sinterings
Stainless steel and nickel steel alloys have become very popular in powdered metallurgy, though selecting the appropriate type of metal for your needs can be difficult. Your sintering provider can help you determine the powdered metal material best suited to your design and specifications.
At Allied Sinterings, we specialize in custom miniature parts for commercial, industrial, and consumer markets. Using state-of-the-art technology in our environmentally controlled facility, our highly experienced technicians can handle virtually any custom powdered metal request, from assemblies and sub-assemblies to precision components for medical devices and process equipment. We can manage low- or high-volume production, offer short lead times on orders over 500 pieces, and can support rush orders when needed.
To see how we can support your project, please contact us today.
An Overview on Powdered Metal Parts & the Powder Metallurgy Process
Powdered metals are alloys processed into a fine, grain-like powder through one of several processes. Primarily made from stainless steel, brass, copper, iron, or bronze, these metals can be blended with other alloys to achieve the desired material properties and characteristics for a particular application. Offering greater flexibility in material usage and mechanical properties, powdered metal parts can be highly customized and easily reproduced while yielding high-strength, cost-effective components.
Manufacturing High Strength Parts
Powder metallurgy (PM) refers to the manufacturing process by which powdered metals or metal blends are formed to desired specifications through a unique combination of heat and compression to create parts and components that offer improved strength over traditionally forged alternatives. The process is shorter than other manufacturing techniques, with primary steps including the following:
Metals are powdered through solid-state reduction, atomization, electrolysis, or chemical treatments like oxide reduction and thermal decomposition.
Powders are blended with other metals, alloying agents, and lubricants to reduce friction and increase fluidity while yielding a homogeneous mix that will be fed into a rigid toolset for processing.
The metal blend is compacted into the appropriate geometry using dies, punches, hydraulic presses, or other consolidation measures.
Compacted pieces are sintered in a controlled atmosphere using extremely high temperatures to metallurgically bond the particulates.
Parts are subjected to secondary operations depending on the requirements of their final application.
The PM process is recognized as being environmentally friendly as it produces harmless bi-products of nitrogen and hydrogen while also limiting production waste by utilizing more than 97% of the material that enters the process.
Heat Treatments & Finishing Options
After sintering, parts may undergo additional heat treatments or finishing to increase material strength and hardness, improve corrosion resistance, boost part tolerance, enhance surface finish, and more. Secondary operations include things such as:
Heat treating: quenching and tempering, steam treating, furnace brazing, etc.
Machining: drilling and tapping, turning, milling, or grinding
Impregnation: oil or resin
Finishing: deburring, tumbling, burnishing, coating or plating, welding, etc.
The Benefits of Powdered Metal Manufacturing
The PM process offers a host of advantages over traditional metal manufacturing practices like forging or die-casting. These benefits include:
Cost-effectiveness: PM reduces energy consumption, improves material utilization, and contains fewer steps than other manufacturing approaches, all of which help lower the impact on the bottom line by trimming costs up to 70%.
Higher degree of customization: From the creation of unique alloy and lubricant blends designed to meet the material properties of a specific application to the ability to easily produce complex geometries like irregular curves and radial projections, key-ways, splines, counter bores, bosses, axial projections and more, PM allows for greater part customization than other metal manufacturing methods.
Minimal machining requirements: With a superior ability to achieve close tolerances, less machining is necessary to produce a final product.
Superior surface finish: Net-shaping and tolerance adherence contribute to a reduction in machining needs, which in turn improves surface finish.
Repetitive accuracy: The process is suited to moderate- to high-volume production with excellent repetitive accuracy.
Materials can be further tailored: Secondary operations allow components to undergo any additional treatments necessary to draw out the material properties most critical for an application’s success, like ductility or hardness.
Custom Powdered Metal Parts From Allied Sinterings
Powdered metal parts provide many advantages that improve part quality and uniformity, shorten production times, and cut down project cost over other manufacturing methods. Allowing for extensive customization and providing repetitive accuracy, powdered metal parts are appropriate in various applications.
At Allied Sinterings, Inc., we apply state-of-the-art powered metal technology to the manufacturing of assemblies, sub-assemblies, medical devices, tools, circuit breakers, and more using custom-blended and brass powders, copper-infiltrated materials, steel, and copper steel. With three sintering furnaces and 42 high-precision presses, an in-house tool room, and a complete tumbling/finishing department, our environmentally controlled facility can manufacture precision parts with outside diameters up to 1.25″, heights up to 1″, and tolerances of ±0.001″.
For more information on custom powdered metal parts or our PM capabilities, contact us today.