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Parker Chomerics CHOFORM 5575 Form-In-Place EMI GasketParker Chomerics is delighted to debut CHOFORM® 5575, an all-new form-in-place EMI gasket at electronica, the world's leading trade fair and conference for electronics. Located in Munich, Germany, electronica brings together nearly 80,000 visitors from 90 countries to discuss the industry’s latest market and technology topics.

What is CHOFORM 5575?

CHOFORM 5575 is a silver-plated aluminum filled, electrically conductive form-in-place gasket. Form-in-place gaskets are dispensed using an automated system and provide reliable electromagnetic interference (EMI) protection for packaged electronic assembles. They are ideal when isolation and complex cross section patterns are required, such as on automotive advanced driver-assistance systems (ADAS) modules or telecommunications boxes.

Good for high temperature, galvanic corrosion

CHOFORM 5575 brings exciting new technology, providing premier EMI shielding over a broad frequency range in high temperature environments up to 125° C (257° F).  CHOFORM 5575’s patented silver-plated aluminum filler technology allows for exceptional galvanic corrosion resistance when mated to an aluminum substrate, making this an ideal product for aluminum castings or airframes.

CHOFORM 5575 joins the family of Parker Chomerics CHOFORM dispensed form-in-place (FIP) EMI shielding gaskets, which are known to provide the lowest total cost of ownership for small cross section and complex pattern applications. From engine control modules (ECMs) to telecom infrastructure, to advanced avionic systems, CHOFORM is the designer’s first choice in form-in-place EMI gasket technology.

See it at electronica 2018

Be sure to visit Parker Chomerics at electronica, November 13-16, 2018 in Munich, Germany, in hall A2, stand 432 to see CHOFORM 5575, as well as the latest EMI shielding and thermal interface materials products from Parker Chomerics.

 

 

Jarrod Cohen

 

 

This blog was contributed by Jarrod Cohen, marketing communications manager, Parker Chomerics Division.

 

 

 

Related Content:

Top Three Design Tips for Corrosion Resistant EMI Protection

New Essential Handbook for EMI Shielding Applications

EMI Shielding Caulk Delivers Superior Performance in Military Radar Systems

 

Discover the CHOFORM Family of Form-In-Place EM Gaskets

 

 

 

 

New at electronica 2018: CHOFORM 5575 Form-In-Place EMI Gasket

Read More

Parker Chomerics CHOFORM 5575 Form-In-Place EMI GasketParker Chomerics is delighted to debut CHOFORM® 5575, an all-new form-in-place EMI gasket at electronica, the world's leading trade fair and conference for electronics. Located in Munich, Germany, electronica brings together nearly 80,000 visitors from 90 countries to discuss the industry’s latest market and technology topics.

What is CHOFORM 5575?

CHOFORM 5575 is a silver-plated aluminum filled, electrically conductive form-in-place gasket. Form-in-place gaskets are dispensed using an automated system and provide reliable electromagnetic interference (EMI) protection for packaged electronic assembles. They are ideal when isolation and complex cross section patterns are required, such as on automotive advanced driver-assistance systems (ADAS) modules or telecommunications boxes.

Good for high temperature, galvanic corrosion

CHOFORM 5575 brings exciting new technology, providing premier EMI shielding over a broad frequency range in high temperature environments up to 125° C (257° F).  CHOFORM 5575’s patented silver-plated aluminum filler technology allows for exceptional galvanic corrosion resistance when mated to an aluminum substrate, making this an ideal product for aluminum castings or airframes.

CHOFORM 5575 joins the family of Parker Chomerics CHOFORM dispensed form-in-place (FIP) EMI shielding gaskets, which are known to provide the lowest total cost of ownership for small cross section and complex pattern applications. From engine control modules (ECMs) to telecom infrastructure, to advanced avionic systems, CHOFORM is the designer’s first choice in form-in-place EMI gasket technology.

See it at electronica 2018

Be sure to visit Parker Chomerics at electronica, November 13-16, 2018 in Munich, Germany, in hall A2, stand 432 to see CHOFORM 5575, as well as the latest EMI shielding and thermal interface materials products from Parker Chomerics.

 

 

Jarrod Cohen

 

 

This blog was contributed by Jarrod Cohen, marketing communications manager, Parker Chomerics Division.

 

 

 

Related Content:

Top Three Design Tips for Corrosion Resistant EMI Protection

New Essential Handbook for EMI Shielding Applications

EMI Shielding Caulk Delivers Superior Performance in Military Radar Systems

 

Discover the CHOFORM Family of Form-In-Place EM Gaskets

 

 

 

 

New at electronica 2018: CHOFORM 5575 Form-In-Place EMI Gasket

Read More

Parker Chomerics Extruded ElastomersThere are many electromagnetic interference (EMI) shielding elastomer gasket mounting techniques that offer designers reliable, cost-effective choices in both materials and component assembly. These options offer aesthetic choices and accommodate packaging requirements such as tight spaces, weight limits, housing materials and assembly costs. Most EMI shielding elastomer gaskets attach using easily repairable systems. Take a look at the list we've compiled of the seven most common elastomer EMI shielding gasket mounting systems below.

Pressure-Sensitive Adhesive (PSA)

Pressure Sensitive adhesive

This quick, efficient attachment strip offers superior flexibility in attaching molded elastomer sheets, cut parts, and extruded conductive elastomers. But beware, Parker Chomerics does not generally recommend the addition/use of pressure sensitive adhesive.

 

 

Friction fit in a groove

Friction Fit in a GrooveFriction fit in a grove prevents the over-deflection of the gasket. A retaining groove will be required to be designed into the application, and this mounting choice is ideal for molded and extruded conductive elastomers. 

 

 

 

 

Adhesive compounds

Adhesive CompoundsAdhesive compounds are ideal for spot bonding non-conductive or conductive adhesive and are ideal for all conductive elastomer materials. It is important to select an adhesive suitable to adhere to either silicone or fluorosilicone, regardless of whether it is a non-conductive or conductive adhesive.

 

 

 

Robotically dispensed form-in-place conductive elastomer

Form-in-place EMI GasketForm-in-place (FIP) automated technology such as Parker Chomerics CHOFORM® applies high-quality conductive elastomer gaskets to metal or plastic housings with robotic precision. FIP is widely used in compartmentalized enclosures and other tightly packaged electronic devices in military, telecom, transportation, aerospace, and life science applications.

 

 

 

Friction fit on tangs

Friction Fit on Tangs

Friction fit on tangs requires special design consideration, but it does accommodate thin walls and intricate shapes. 

 

 

 

 

 

Spacer gaskets

Spacer GasketSpacer gaskets are fully customized, integral spacers made from either conductive elastomer or plastic, and provide economical EMI shielding and grounding in small enclosures. Locator pins ensure accurate and easy installation, manually or robotically. 

 

 

 

 

Rivets/Screws

Rivets and ScrewsRivets or screw mounting requires integral compression stops and mounting holes on the flange.

 

 

 

 

 

For more information, visit Parker Chomerics Division or contact us directly.

 

Jarrod Cohen


 

This blog was contributed by Jarrod Cohen, marketing communications manager, Parker Chomerics Division.

 

 

 

 

Related Content:

New Essential Handbook for EMI Shielding Applications

Top Three Design Tips for Corrosion Resistant EMI Protection

Design Decisions Relating to EMC Shielding

7 Most Common EMI Shielding Elastomer Gasket Mounting Choices

Read More

Elastomer EMI GasketsPressure sensitive adhesive, more commonly known as PSA, is adhesive which forms a bond when pressure is applied, to join the adhesive with an EMI gasket. As the name "pressure-sensitive" indicates, the degree of bond is influenced by the amount of pressure which is used to apply the adhesive to the surface.

When it comes time to focus in on gasket electrical conductivity, it is generally not recommended to use PSA with an EMI shielding gasket. This is because the strip of adhesive inhibits true contact of the EMI shielding gasket with the mating surface, thereby decreasing the performance of the gasket. However, if a PSA system is deemed necessary, then the following guidance should be considered.

Advantages of PSA
  • Eliminates fasteners or other adhesives.
  • Can function as a “third hand” to facilitate difficult installations.
  • Available with silicones or fluorosilicones as a permanent attachment method.
  • Quick stick – readily adheres to clean surfaces.
  • Conformable adhesion to curved surfaces.
  • Resists humidity, moisture, natural elements.
  • Eliminates alternative RTV solvent emissions and long set-up times.
Disadvantages of PSA
  • Not available for round cross-sections, as there is little surface area to stick to.
  • Not recommended for applications where solvent resistance is essential.
  • Not recommended for applications where resistance to excessive abuse due to moving parts or traffic is required.
  • Adds a shelf life to the sheet stock elastomer.
  • Not available with EPDM binders.

Depending on how they are used, a PSA system may reduce the gasket through flange conductivity and/or shielding effectiveness to varying degrees.  Applications such as an EMI connector gasket which requires the lowest electrical resistance ground connection should not incorporate a PSA system.

Overall, the use of PSA as an attachment method for elastomer materials is meant to aid in initial assembly operations vs. a long term means of permanent attachment. Generally, you can expect the minimum deflection of the gasket may need to be increased to obtain desired shielding results.

PSA on Elastomer EMI Shielding Gasket

 

 

 

 

 

 

 

 

 

 

 

Jarrod Cohen

 

 

This blog was contributed by Jarrod Cohen, marketing communications manager, Parker Chomerics Division.

 

 

 

 

Related Content:

Design Decisions Relating to EMC Shielding

New Essential Handbook for EMI Shielding Applications

Top Three Design Tips for Corrosion Resistant EMI Protection

Pressure Sensitive Adhesives and Elastomer EMI Gaskets: What You Need to Know

Read More

The Difference Between Thermal Conductivity and Thermal Impedance, Parker Chomerics DivisionThermal Interface Materials (TIMs) are useful for thermal management in electronic components, as they enhance heat transfer from a heat-generating component to a heat dissipater, or heat sink. One important aspect when selecting a TIM for your application is knowing the material’s ability to transfer heat, which is often given by way of thermal conductivity and/or thermal impedance.

Across the industry, manufacturers often publish thermal conductivity in units of Watts / meter-Kelvin as well as thermal impedance in units of °C – inches2 / Watt on their datasheets. So, what is the difference between these two, and how should you consider them when selecting a TIM?

Thermal conductivity is a material property and describes the ability of the given material to conduct heat. Therefore, when a material’s thermal conductivity is high, the material is a better thermal conductor. This property is independent of material size, shape or orientation in a homogeneous material, and because of this, thermal conductivity is an idealized value.

To understand thermal impedance, we must first understand thermal resistance and thermal contact resistance.

  • Thermal resistance is another inherent thermal property of a material, and is the measure of how a material of a specific thickness resists the flow of heat. Since TIM thickness is directly related to the resistance, thinner TIMs transfer heat more efficiently than thicker ones.
  • Contact resistance is specific to the interfaces where a TIM meets the heat-generating component and the heat sink. In reality, neither of these components are perfectly flat or smooth, therefore these surface irregularities create micro-air voids when in contact with the interface material, reducing the effectiveness to transfer the heat (air is a very poor thermal conductor).

Therefore, the thermal impedance of a material is the sum of its thermal resistance and all contact resistances. When a material’s thermal impedance is lower, the material is a better thermal conductor in that application. Based on this, it is understandable that factors such as surface roughness, surface flatness, clamping pressure, presence of adhesive, non-homogeneous, and material thickness all have large impacts on the material’s thermal impedance. Thus, thermal impedance is a better “real world” thermal property, as it accounts for more variables specific to the application.

In summary, when comparing different TIMs for a specific application, you can begin with thermal conductivity for general comparisons, but having thermal impedance versus pressure data will be far more accurate to your “real world” conditions.

The Difference Between Thermal Conductivity and Thermal Impedance, Parker Chomerics Division

 

 

 

 

 

 

 

 

For more information, visit Parker Chomerics Division or contact us directly. 

 

The Difference Between Thermal Conductivity and Thermal Impedance, Jarrod Cohen Head Shot

 

 

This blog was contributed by Jarrod Cohen, marketing communications manager, Parker Chomerics Division.

 

 

Related Content:

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The Difference Between Thermal Conductivity and Thermal Impedance

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Metal-to-plastic Conversion Benefits for Automotive Engineers, Transmission pieces converted from metal to plasticFor automotive engineers looking to reduce vehicle weight, metal-to-plastic conversion is a win-win. At the highest level, injection plastic molds are capable of producing multiples of millions of parts required for automotive programs with ease. Typically, a single tool can support a program for its entire life-cycle, meaning you only must go through the cost and design of tooling just once.

In traditional metal fabrication, you have stamping and die casting, both of which require tool refurbishment, at what can amount to a very significant cost. Although injection mold tooling can be relatively expensive, it is not more expensive than die cast tools and/or stamping tools.

Typically, injection molds will last many times longer than metal tooling. Injection mold tooling are also more flexible than other types of tools, allowing you to incorporate many types of features into a part so that no secondary machining, coating and/or forming is required after the molding operation. And depending on the type of plastic material you select; you can realize excellent strength to weight properties.

Why is that important?

Metal has been used for decades now to machine and fabricate parts that need to last long past the product’s life cycle. Today, metal replacement parts, better known as metal-to-plastic replacement technology, offers a lighter, more cost effective solution that is often superior to the metal part it replaces.

Take for instance the cylinder head cover pictured. It has undergone a metal-to-plastic transformation, featuring multiple cable management mounts, coupled with the elimination of the spark plug tube mounting point, which has vastly decreased noise from the engine.

But most importantly, its weight has decreased 47% - a significant weight savings by automotive manufacturing standards.

Design support is critical

Selecting the right injection molding plastic resource is critical, especially for companies that do not have in-house plastic expertise. Support engineers can ensure that the plastic part is properly designed for optimum molding capability, and look for opportunities to combine multiple parts into one, eliminating cost and manufacturing operations down the line. Plastic engineers can also support the design process with computer aided analysis, such as mold flow and finite element analysis (FEA).

Metal-to-plastic Conversion Benefits for Automotive Engineers, Metal to plastic converted automotive parts

Finally, plastic engineers can help with selecting the correct plastic resin, noting the user environment and required chemical resistance, operating temperature range, and whether there needs to be electrical properties such as conductivity, thermal properties such as heat dissipation and mechanical strength. Plastics offer more functionality with less weight. With plastics, there is a freedom of design not found in metal parts.

Learn more about Parker Chomerics’ injection molded plastic expertise, including engineering support today.

 

 

Jarrod Cohen

 

 

This blog was contributed by Jarrod Cohen, marketing communications manager, Parker Chomerics Division.

 

 

 

 

Related Content:

Best Conductive Plastics: Five Things to Look For

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Metal-to-Plastic Conversion Benefits for Automotive Engineers

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