Effects of Grain Size on the Mechanical Strength of the Precipitated-Harden Stainless Steel

• Main Authors: Lan, Yuan-Shiau, 藍元孝
• Other Authors: Chao, Chih-Yeh
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/19629430527585322226

碩士 === 國立屏東科技大學 === 機械工程系所 === 104 === The characteristic time (CT) of Fairway wood is not restriction resulting to thinning design. In addition, the Fairway wood would be usually producted by use of the pecipitated-harden stainless steel such as Custom 455, Custom 465 and 17-4PH. However, the grain sizes of the alloys would play an improtant role on the thinning design, of which being various high- temperature heated treatment. Therefore, the purposes of the present studies are focused on the effects of Grain Size on the Mechanical Strength of the Precipitated-Harden Stainless Steel. Some results are described as following: 1. The tensile strength, yield strength and elongation of Custom 455 stainless steel are between 140 to 164ksi, 130 to 149ksi and 10.7 to 11.5% respectively after heat treatment in different temperature. The relationship between Mechanical properties and grain size is σY = 125.4 + 101.6D-1/2, and the grain size is between 12.7 to 59.2μm. 2. The tensile strength, yield strength and elongation of Custom 456 stainless steel are between 145 to 155ksi, 140 to 143ksi and 11.7 to 12.4% respectively after heat treatment in different temperature. The relationship between Mechanical properties and grain size is σY = 139.5 + 310D-1/2, and the grain size is between 44.5 to 50.μm. Incidentally, Grain size can be observed just little change. Because grain size is too large impact (no heat treatment ), it has an upper limit. 3. The tensile strength, yield strength and elongation of Custom 456 stainless steel are between 157 to 165ksi, 142 to 150ksi and 40 to 16% respectively. The relationship between Mechanical properties and grain size is σY = 141.6 + 73.4D-1/2, and the grain size is between 14.0 to 38.9.μm. 4. These results are in compliance with Hall-Petch equation, and we observe the tensile strength, yield strength and elongation of 1770 low-alloy steel are between 151 to 158ksi, 140 to 150ksi and 11.0 to 11.2% respectively after heat treatment in different temperature. The relationship between Mechanical properties and grain size is σY = 125.4 + 101.6D-1/2, and the grain size is between 12.7 to 59.2μm. The result is the same.