CRR Blog

Working with Toyota’s High Strength Steel and Ultra High Strength Steel

AUTOMOBILE MANUFACTURING CONTINUES TO ADVANCE WHEN IT COMES TO WEIGHT SAVINGS. The materials used are lighter and sturdier than ever before. It is common to find UHSS (Ultra High Strength Steel) where previous models used HSS (High Strength Steel). The use of UHSS continues to grow and so do expectations for quality.

For example, the new federal mandate of CAFÉ (Corporate Average Fuel Economy) standards requires that passenger vehicles achieve 54.5 miles per gallon by 2025. And while manufacturers are exploring powertrain advances, they also know that lowering the weight of the vehicle will help them achieve the fuel efficiency requirement.

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Metallurgists have played a vital role in developing steels that are lighter and equally capable of controlling collision energy forces for occupant protection. Toyota has been increasing its use of Ultra High Strength Steel (UHSS) in many models. Now on the 2016 Prius and Tacoma, you will find UHSS rated as high as 1480 MPa also known in the industry as Advanced Ultra High Strength Steel (AUHSS).

For the 2016 Tacoma, the cabin is constructed of 440 MPa, 590 MPa, 980 MPa and 1480 MPa* steel (*Toyota’s first on this vehicle). The strength of the cabin reinforcements has tripled when compared to previous models. As you can imagine, the use of UHSS also requires special attention to repair and welding methods. When UHSS structural properties are lessened by deformation from a collision or improper sectioning and welding, the UHSS can no longer perform as it was designed, which could affect occupant safety in a subsequent collision.

This is why Toyota published CRIB (Collision Repair Information Bulletin) #175 titled: HSS & UHSS Cabin Reinforcement Repair & Replacement, which you can find at www.crrtraining.com. This bulletin addresses the safety concerns and standards associated with repair decisions that accompany damage to HSS and UHSS cabin reinforcements. Model-specific Collision Damage Repair Manuals provide the location and strength ratings for HSS and UHSS in the Structural Outline section.

Once a reinforcement is deformed by an impact the integrity of the steel is compromised and would be made worse if it were to be straightened by any repair method. This is why damaged HSS and UHSS occupant cabin reinforcements must be replaced with only Genuine New OE Service Parts. Gone are the days of reducing repair cost by repairing instead of replacing components that contribute to occupant safety.

Now more than ever, all stakeholders involved in making vehicle repair decisions need to be aware of OE repair requirements and specifications. Toyota publishes model-specific Collision Damage Repair Manuals and CRIBs that are available to all collision repair professionals through TIS (Toyota’s Technical Information System) at www.techinfo.toyota.com.

To further awareness of this and many other important collision repair topics, Toyota’s Collision Repair & Refinish Team of expert trainers offer Web-Based and Instructor-Led Training to all collision repair professionals. Visit www.crrtraining.com to learn how to sign up.

 

OTHER WAYS TO GET INFORMATION. Visit our trainers this year at NACE | CARS Expo, booth (#939)—August 9-13.