CRA Innovation & Technology – USA
Material Sciences Corporation Chief Technical Officer Matt Murphy last year said his company has begun to produce “Quiet Aluminum” able to reduce the need for other dampening products.
The new substance joins MSC’s “Quiet Steel” portfolio and can be found in the new Ferrari SF90 Stradale platform, Murphy told a November 2019 SCRS OEM Collision Repair Technology Summit session recently made available on YouTube.
The laminated metals mean an OEM doesn’t need “the spray-on products, the peel-and-sticks, an aftermarket Dynamat, these types of things that we use to quiet down a body,” Murphy said. He presented examples where such treatment added 5 pounds and 9 pounds of weight. They also add cost and labor for an OEM, he said.
Ferrari appeared to give a nod to the Quiet Aluminum when it announced the multi-material plug-in hybrid SF90 in May 2019. The reference came after Ferrari noted it had to offset more than 595.2 pounds added by the hybrid system.
“The chassis has been completely redesigned with a multi-material and multi-technology approach to absorb the extra stresses associated with the new power unit and the introduction of AWD. A number of technological innovations have been introduced, not least hollow castings, which replace the traditional ribbed castings. Other new solutions include an all-carbon-fibre bulkhead between the cabin and the engine and two new aluminium alloys, one of which is a high-strength 7000 series alloy for some of the sheet metal. As a result, the SF90 Stradale chassis boasts 20% higher bending stiffness and 40% higher torsional rigidity than previous platforms without any increase in weight. This has significant advantages for the car’s dynamics. NVH (noise, vibration, harshness) characteristics have also been improved by the use of a new alloy known as ‘quiet aluminium’ for the floor pan.”
Repairers might have already seen the company’s Quiet Steel. Murphy said his company has been supplying the substance for the Ford F-150 firewall dating back to the 2004 edition — and it continued to do so even after the F-150 went aluminum for the 2015 model year.
Aluminum is lighter and is less stiff than steel, raising noise and vibration concerns. Research found an aluminum firewall would require 8-10 inches of space to achieve the same cab quietness as the 2014 steel F-150, according to Murphy.
So Ford kept the firewall Quiet Steel, eliminating the need for damping treatments or thicker aluminum, according to an MSC slide. However, the mixed-material design — a steel firewall surrounded by aluminum — led to different coating and joining for the Quiet Steel, according to Murphy’s presentation.
The Quiet Steel firewall on the aluminum F-150 is green, the result of an organic coating meant to resist the galvanic corrosion produced when steel and aluminum come into contact, according to a slide. It is now attached by self-piercing rivets, clinch nuts and adhesive, according to the slide; Murphy said the part had been spot-welded when the F-150 was all steel.
“We had to solve a lot of technical challenges around mixed metals and galvanic corrosion for this,” Murphy said. But the part has “outstanding acoustic performance” and outperforms aluminum.
MSC also has developed another laminated steel of note for collision repairers: the “Smart Steel” found in the roof bows of the 2020 Ford Escape. Murphy discussed it as well during the SEMA Week presentation; see our past coverage and view the SCRS video for more details.
Society of Collision Repair Specialists YouTube channel, March 19, 2020
Ferrari, May 29, 2019
Featured image: Material Sciences Corporation Chief Technical Officer Matt Murphy raps on a Quiet Steel firewall at the 2019 SCRS OEM Collision Repair Technology Summit to demonstrate how quiet the laminated metal is. (John Huetter/Repairer Driven News)
Credit to RepairerDrivenNews.