OREANDA-NEWS.  July 12, 2012. 300M steel developed by Baosteel Special Materials Co., Ltd. used for landing gear of C919 China-made large passenger aircraft passed the Transition Review organized by Commercial Aircraft Corporation of China, Ltd. Opinions form the Review experts indicate that various performance indexes and batch stability of 300M steel developed by Baosteel Special Materials meet the technical requirement of COMAC, it is agreed to get into installation and application research period, reported the press-centre of Baosteel.    

Therefore, Baosteel Special Material becomes the first material supplier who has passed the Review, which marks a key step toward qualified product list of COMAC. 
 
C919 China-made large passenger aircraft is a short-medium range commercial trunk liner that can claim indigenous intellectual property and one of the major science and technology programs for determination of National Guideline on Medium- and Long-Term Program for Science and Technology Development (2006-2020).

Aviation industry of China has experienced more than 50 years of development, aeronautic material and manufacture process has developed from the imitation state to independent development status, which has laid a firm foundation for the development of large aircraft in China. As one of the main supporting units for aeronautic material in China, Baosteel Special Material has involved in advanced research of relevant material at the beginning of C919 project.       
   
Landing gear is one of the key parts of the airplane, impact force beared by the landing gear can be as high as 2 to 3 times of the gravity when the plane landed. Therefore, it has extremely harsh requirement on the stability, impact resistance and fatigue resistance of steel for landing gear, as well as the manufacture difficulty and quality control. Up to now, there's no material supplier supplied with steel for landing gear of airplane officially. Under the direction of Shanghai Aircraft Design and Research Institute of COMAC, Baosteel Special Material has finished compiling of process control document according to the requirement of civil aeronautic material system, guaranteed the stability of product quality through curing the key process parameters of each procedure, and established industrialized manufacturing and equality management system step-by step, which meets the requirement of civil aeronautic material.       
  
Baosteel Special Material had taken the manufacture process prevalent in the world as the goal at the beginning of developing 300M steel for landing gear in 2005. Baosteel adopts the process flow of arc furnace + self-consumption and has carried out industrial test for nearly 30 furnace batches up to now. Based on the mass data, Baosteel Special Material has formed and cured the production process of 300M steel for landing gear step-by-step and basically has the ability to supply landing gear for civil aircraft.