| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a magnesium alloy material that is thick and excellent in corrosion resistance and roughening resistance, and a method for producing the same. <P>SOLUTION: The magnesium (Mg) alloy material (typically a Mg alloy plate) has a plate-shaped section having a thickness of at least 1.5 mm. When a surface region is defined as a region within 1/4 of thickness in the thickness direction from the surface of the plate-shaped section and an inner region defined as the remaining section, the ratio O<SB POS="POST">F</SB>/O<SB POS="POST">c</SB>of the base surface peak ratio O<SB POS="POST">F</SB>of the surface region to the base surface peak ratio O<SB POS="POST">c</SB>of the inner region (orientation joint of the (002) surface) satisfy the relation: 1.5<O<SB POS="POST">F</SB>/O<SB POS="POST">c</SB>. In the Mg alloy material, the surface region of the plate-shaped section is composed of an aggregate structure in which the (002) surface, which is the base surface of Mg alloy crystals, is strongly oriented in comparison with the inner region. The alloy material is excellent in corrosion resistance because the grain size in the surface region is typically smaller than that in the inner region, and due to the excellent roughening resistance, a molded product excellent in surface quality can be obtained by carrying out press working. A plate-shaped Mg alloy can be obtained by rolling a twin-roll continuous cast material for a plurality of passes with the rolling reduction for all the passes being ≤25%. <P>COPYRIGHT: (C)2012,JPO&INPIT |
