GM uses third-gen advanced high-strength steel in new vehicle for China

General Motors is applying third-generation advanced high-strength steel to the new Chevrolet Lova RV from SAIC-GM, thereby reducing the weight of selected body components by approximately 20 percent. The recreational vehicle (RV) was launched on November 19.

The new steel offers a superior balance of strength and ductility as compared to the first generation of high-strength steels. The fuel economy of a vehicle is generally considered to increase by 6 to 8 percent for every 10 percent reduction in body weight.

In 2009, the carmaker began encouraging steel manufacturers to produce third-generation advanced high-strength steel with superior formability and tensile strengths of 1,000 MPa and higher for vehicle bodies.

Among all the state-of-art steel-making processes, the GM China Science Lab in Shanghai identified the Quench and Partition (Q&P) process as one of most promising solutions for producing third-generation advanced high-strength steel. Through a specially-designed quenching and partitioning treatment, retained austenite can be stabilised in the steel microstructure at room temperature, which significantly improves the formability of steel. In 2011, GM China Science Lab joined GM’s Pan Asia Technical Automotive Center (PATAC) joint venture, Baosteel and Tongji University to establish an expert team to develop solutions for introducing Q&P steels into GM vehicles.

Research groups within the GM China Science Lab, GM China Advanced Technical Center (ATC), and the GM Warren Technical Center in the United States collaborated on research and development of third-generation advanced high-strength steel.  This global development network was instrumental in the successful implementation of the advanced steel technology in GM vehicles.

In the past, nearly 25 years of research and development were required to go from initial steel development concepts to production of the first-generation high-strength steels such as dual-phase steel. Through open innovation, GM and its partners have been able to dramatically shorten the concept-to-production process of third generation steels.

According to Dr. Ming Liu, Lab Group Manager of the Advanced Materials Research Group at GM China Science Lab, “GM has recorded major achievements through this open innovation. With this continuous technical development, innovative technologies will be applied to GM products at an increased pace.” 

GM says it has also contributed significantly to the application of key technologies by studying materials, microstructures and assessing their performance. Findings from these investigations are now being applied to the development of third-generation 1,200 MPa Q&P steel. In addition, assessment methods that precisely measure the performance of third-generation advanced high-strength steel, especially in terms of crashworthiness, have been adopted by a number of steelmakers. Technical learnings such as these are being shared worldwide within GM and will be instrumental to future applications of third-generation steels in GM vehicles around the globe.

According to GM China Science Lab Director John Du, “Safety and fuel economy are two things that vehicle buyers worldwide have made a priority. This has created the need for lightweight, strong and affordable materials.”

Du adds, “The GM China Science Lab has expertise in lightweight technology research. Through open innovation, we have advanced the research, development and application of lightweight automobile technologies. We look forward to partnering with more suppliers to jointly promote technological development.”