Side-impact car door beams are a key component to “survival space” in automobiles during a crash. Leveraging higher strength steels for side-impact beams offers car OEMs a cost-efficient way to achieve 5-star crash safety performance.
Side-impact automobile collisions, in general, result in more severe injuries than other types of collisions. Severe injuries to both upper and lower body can occur if the survival space is inadequate. Using optimized designs and advanced high strength steel grades for side-impact beams can significantly increase survival space in cars, helping to protect drivers and passengers during side impact crashes.
For a new design for side-impact car door beams, a Tier 1 supplier needed to improve crash test performance, corrosion resistance, and cost efficiency – while lowering weight. Aluminum proved to be too costly, while press hardening steel would require investments in hot-forming presses, as well as slower production times.
Instead, the Tier 1 chose Docol® CR1500M-EG in 1.0 mm thickness. The martensitic 1500 MPa side-impact beams helped the car achieve a 5-star crash safety rating for side impacts while their 1.0 mm thickness kept the car door light in weight. Plus, the electrogalvanized metal coating provides the required level of corrosion resistance at a cost-efficient price point.
The Docol® CR 1200Y 1500T-MS-EG side-impact beam is cold stamped, saving production time, cost and emissions compared to hot stamping. A 3-point bending test verifies how the side-impact beam will perform during a crash, demonstrating the ability to deform without cracking. Image courtesy of KIRCHHOFF Automotive.
This new design for waistline car door side reinforcement features a roll-formed, laser-welded, closed profile beam in hot-dip galvanized Docol® HR700LA-GI. The waistline beam is either 2.0 mm or 3.0 mm thick, depending on the car model. With the high-strength, low-alloy (HSLA) 700 MPa steel, the waistline reinforcement beam achieves 5-star crash test performance and fulfills all current global automotive safety requirements.
Another example of roll-forming AHSS steel into innovative safety profiles: This car door waistline reinforcement beam in Docol® HR700LA-GI features low weight, hot-dip galvanized corrosion resistance, and 5-star crash performance.
The existing design for this side-impact car door beam used CR1200M-EG. To further improve its crash performance and to reduce weight, the OEM is doing trial stamping of Docol® CR1400M-EG in 1.3 mm thickness. In addition to achieving 5-star crash test performance, the beam can be stamped using conventional cold stamping processes, achieving better cost and energy efficiencies compared to hot-stamping or using aluminum.
Side-impact car door beam in Docol® CR1400M-GI: a cold-stamped, corrosion-resistant, cost-efficient solution.
Waistline reinforcement beam: HR 700LA – CR1700M
Side impact beam: CR1180DP – CR1700M – CR2000PHS
In just one to two weeks, you can get trial samples of most of our commercially available AHSS/UHSS steel grades – plus some of our newest, not-yet-released steels.
Our steel grades serve specific design purposes and are chosen by designers for a wide range of automotive applications.
Japanese car OEMs and their Tiers 1s are now cold stamping some body-in-white auto parts made from 1.5 GPa steels. And companies in other parts of the world are running very high strength steels in cold-stamping trials, including for 1.5 GPa and 1.7 GPa side impact beams. These activities demonstrate how cold-forming processes – both cold stamping and roll forming – give carmakers cost- and energy-efficient alternatives to hot-stamping when it comes to ultra-high strength steels.
SSAB offers a full selection of hot-dip galvanized, Galfan®, galvannealed, and electrogalvanized coatings for corrosion protection on many of its Docol® AHSS automotive steel grades.
Martensitic steel combines tensile strengths up to 1700 MPa with good ductility, making it highly efficient for both vehicle lightweighting and improved crash protection — especially in anti-intrusion zones.