What are the advantages of sintered metal?

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Metal sintering is the process of fusing metal powders to create a solid object and involves heat and pressure. The result is a metal object with a near-net shape, meaning it only requires minimal finishing work before being used.

Sintered metals can have many applications, depending on their composition and the way they are produced. In this article, we'll take a closer look at metal sintering, its process, its benefits, and some potential applications.

Powder Metal Sintering Process

The sintering process helps to bind the particles of metal powder together, creating a solid, dense piece.

The powder metal sintering process includes:

1. Choosing a powder composition:

   The metal powder type you use will determine the properties of the finished product, so selecting the right one for your needs is crucial.

2. Compaction:

   Once you've selected the right powder for your needs, the next step is to compact it into the desired shape. It is performed using a die press, which applies pressure to the powder to force it into the desired shape. The amount of pressure and the duration of pressing will vary depending on the powder type and the desired final product.

3. Sintering:

   After the powder is compacted into the desired shape, it is ready for sintering. Sintering is a process of heating the powder to just below its melting point, allowing the particles to bind and form a solid piece. The length of time and temperature at which the powder is heated will vary depending on the powder type and the desired final product.

Benefits of Metal Sintering

Metal sintering offers several advantages over other manufacturing processes. These include:

1. Complex shapes:

   Metal sintering allows for creating complex shapes that would be difficult or impossible to produce using other methods.

2. High dimensional precision:

   It offers high dimensional accuracy, meaning that the finished product will be very close to the desired shape.

3. Reliability and repeatability of large mass production:

   It is a very reliable process, and the finished products are consistent, making it ideal for large-scale production runs.

4. Self-lubrication:

   It can create parts with self-lubricating properties. The powder is compacted under high pressure, creating a dense, tight bond between the particles that helps reduce friction and wear, making self-lubrication possible.

5. Unique and isotropic materials:

   It is used to create unique isotropic materials. These materials have the same properties in all directions, making them ideal for applications where strength and durability are essential.

6. Green technology:

   It&#;s considered a green technology, as it doesn't produce any harmful emissions, making it ideal for companies looking to reduce their environmental impact.

7. Damping vibration:

   It can create parts with vibration damping properties. The powder is compacted under high pressure, creating a dense, tight bond that helps reduce vibrations and noise, making vibration damping possible.

Metal Sintering Applications

Metal sintering is a versatile process that improves the properties of many materials. In particular, sintering often enhances metals' strength, conductivity, and translucency. Its uses involve producing electrical components, semiconductors, and optical fibers.

Metal sintering is a popular choice for 3D printing applications, as it creates custom metal forms. Metal sintering works by melting metal powder one layer at a time, making it ideal for creating complex shapes and structures. Metal sintering also has high accuracy and repeatability, making it suitable for industrial and manufacturing applications.

This technique uses various metals, including aluminum, brass, bronze, and stainless steel. Sintering allows for greater control over the manufacturing process and can result in more consistent products. Additionally, sintering requires less energy than melting the same metal, making it a more environmentally-friendly option.

Sintering can also enhance the properties of various metals. For example, sintering minimizes the porosity of an object's surface. This can improve the strength and durability of the object.

The uses of metal sintering include the creation of:

• structural steel parts
• porous metals for filtering
• tungsten wiring
• self-lubricating bearings
• magnetic materials
• electrical contacts
• dental products
• medical products
• cutting tools.

Metal Sintering with Pacific Sintered Metals

Metal sintering is a process that Pacific Sintered Metals (PSM) specializes in. This process involves heating metal powder just below its melting point, allowing the particles to bond to form a solid mass. PSM has over 65 years of experience in sintering metals, and our team can sinter various metals, including stainless steel, titanium, nickel, and more. We are also able to work with customer-provided materials.

Sintering is a versatile process that creates parts of different shapes and sizes. The process is also relatively quick and efficient, making it ideal for large-scale production. Sintering can also create parts with complex geometries or internal features that would be difficult to produce using other manufacturing methods.

If you&#;re interested in learning more about how metal sintering can improve your part performance. Our team would be happy to discuss your specific needs and see how we can help you take your product development to the next level.

At this point, we all know that powder metallurgy can make small, complex parts for a variety of industries, including:

• Electric motors 
• HVAC
• Automotive
• Firearms
• Lawn and garden

But there are several decisions to be made when considering the most effective metal forming technology for the job. Engineers must look at performance needs and tolerances, as well as budget limitations and production quantities.

Sintering is a required PM process step to improve a part&#;s strength. A compacted PM part is heated in a furnace up to about (typically) º F, after which it might move on to various secondary operations. 

While most PM parts are sintered, not all materials are conducive for sintering. SMC materials lose their magnetic performance when sintered. But that is only one of the many variables when it comes to sintering:

Sintering Advantages and Disadvantages: The Variables

All powder metal parts need to be sintered unless they require the magnetic qualities of soft magnetic composite (SMC) materials. Sintering is a customizable process and will vary depending upon the materials, properties required, and the desired tolerance.

Sintering processes vary from part to part, including changes in:

• The amount of time at temperature
• The temperature itself 
• Atmospheric conditions

Some of the keys to sintering are the creation of metallurgical bonds between materials, reduction of variability, and minimization of part waste. Advances in sintering furnace technology now offer the ability to control the furnace in real-time, which improves these fundamental elements of the sintering process. 

New, advanced systems like these help manufacturers streamline their processes and collect better data about the end quality of your part.

Dashang are exported all over the world and different industries with quality first. Our belief is to provide our customers with more and better high value-added products. Let's create a better future together.

Sintering Considerations: The Material

What is the material system you would use to create a new design PM application? 

Let&#;s begin with a clear distinction of the needs of different part applications.  

High strength structural applications often have requirements of high:

• Tensile strength
• Fatigue strength
• Particle hardness  

These core requirements necessitate higher alloy and carbon contents and strength-inducing heat treatments. Unfortunately, these requirements also lead to significantly reduced DC magnetic performance.

Improving Performance With Sintered Soft Magnetics

However, not all parts have specific strength requirements. Thinking about parts that need good magnetic performance, these sintered soft magnetic parts often need:

• Very low carbon content
• High-purity materials
• Heat treatments to optimize magnetic properties

Certain alloying elements in iron such as phosphorus and silicon can improve magnetic performance and also give minor improvements in structural strength, but not to the level possible with higher-strength structural materials.   

This type of material might be appropriate for applications like armature housing or fuel injection systems with magnetic solenoids. 

Solenoids

Sometimes the right magnetic performance can be achieved with a variety of materials; in many instances an iron-phosphorus will satisfy the requirements of these applications. However, certain higher performance or faster responding solenoids will require the properties of an iron-silicon material that has been sintered at ultra-high temperatures to meet these demanding  levels of magnetic performance. 

One of the primary allures of powder metal is the ability for unique material formulations and shape-making capabilities. Powder mixtures can be tailored to meet specific needs, and paired with the proper sintering, can greatly improve your overall performance to make a better, longer-lasting part.

Standard Sintering vs. Sinter Hardening

With standard sintering, we focus on creating metallurgical bonds between materials. Sinter hardening takes that process a step further to provide heat-treated properties to a sintered part.

Sinter hardening is an accelerated cooling process that increases the metal&#;s hardness to improve resistance to deformation under stress. Sinter hardening takes advantage of the intrinsic heat put into the part during the sintering step and combines this with an accelerated cooling to then effectively heat treat the part to achieve high hardness and strength.

Conventionally, you&#;d have to form a part, sinter, and heat treat it. But with sinter hardening, we can eliminate a thermal cycle and rely on PM&#;s inherent net shaping capabilities to eliminate machining after sinter hardening. 

Plus, the part-to-part variation is much lower when using sinter hardening as compared to traditional sinter-heat treat-quench processes. 

A caveat of sinter-hardened parts: traditional machining operations can be difficult due to the hardness of the part.

High-Temp Sintering vs. Ultra-High-Temp Sintering (UHTS)

Traditionally, people think that high-temp sintering utilizes temperatures of -ºF. Engineers have realized high-temp sintering offers an improvement in mechanical qualities over the ordinary sintering process, but often still falling short of other metal-forming technologies such as forging. 

Technological improvements in powder metallurgy have led to the development of ultra-high-temperature sintering (UHTS). Just picture high-temp sintering, but after it&#;s had a lot of coffee. 

Utilizing ultra-high-temp sintering, the compacted ferrous powder is sintered at temperatures approaching ° F, far above normal sintering temperatures. As the temperature rises, so does the cost of sintering, but this cost is often offset by the dramatic increase in part performance. 

It also allows the PM process to use non-traditional alloying elements that can give unique combinations of strength, ductility, hardness, and heat treat response. 

If the current part works with conventional sintering, you probably can't justify the cost of upgrading to UHTS. But potential DC magnetic applications and high-strength components could benefit from new material possibilities only achievable with UHTS.

Other Uses of Sintering for Powder Metallurgy

Sintering is also suited for unique parts that require low-density, high-porosity gas flows. 

Using a protective mask analogy, this would be similar to breathing through an n95 mask vs. a conventional mask. The looser the weave, the easier it is to breathe and let particles through. The tighter the weave, the harder it is to breathe and for particles to move through. 

With a filter, you want certain things trapped outside, so a high-porosity material is a must. Proper sintering can not only create a tighter, more compact shape -- but can be tailored to create the necessary open porosity to optimize the often conflicting properties of good flow and filtration.

Improving Part Tolerances and Efficiency with Sintering

When it comes to decoding the benefits of sintering, work with an expert powder metallurgy consultant that can recommend the best approach for cutting costs and fulfilling your needs. (Note that only Horizon&#;s furnace technology has the unique capability to both sinter-harden and sinter at ultra-high temps.)

To learn more about sintering, take a look at our new guide!

Are you interested in learning more about Sintered Metal Fiber? Contact us today to secure an expert consultation!