Fatigue and fracture toughness of Alloy 0Cr15Ni25MoTiAlVB (A-286) precipitation-hardened stainless steel
Alloy 0Cr15Ni25MoTiAlVB (A-286) precipitation-hardened stainless steel is a type of stainless steel alloy that is composed of 0.06–0.13% carbon, 14.7–17.4% chromium, 2.0–2.5% nickel, 4.2–5.5% molybdenum, 0.2–0.5% titanium, 0.06–0.09% aluminum, 0.5–1.5% vanadium, and 0.04–0.08% boron. A-286 is often used in applications requiring high strength and good corrosion resistance such as jet engine components and medical implants. As part of the alloy’s composition, molybdenum and titanium provide time-delayed strengthening, allowing A-286 to experience improved fatigue performance.
Fatigue is the weakening of a material due to cyclic loading, which is typically seen in rotating components. To understand fatigue performance in A-286 stainless steel, a series of tests (usually in the form of tension-tension or four-point bend) can be performed on laboratory-scale specimens. The results of these tests will provide information about the characteristics of the material’s fatigue performance, including fatigue limit, fatigue strength, and stress-cycles to failure. It is the combination of these results that will help engineers design the appropriate component for the application to ensure it is able to withstand the cyclic loading it will experience during service.
Fracture toughness, on the other hand, is the amount of energy required to cause a crack to propagate in a material. For A-286 stainless steel, fracture toughness is tested using a tested triangle specimen. This test determines the material’s resistance to cracking by assessing the amount of force necessary to cause a crack to propagate through a standard-sized specimen. The results of this test can then be compared with those of other stainless steels, allowing engineers to determine which grade is best suited for a specific application.
Alloy A-286 precipitation-hardened stainless steel is a commonly used material in applications requiring high strength, good corrosion resistance, and improved fatigue and fracture toughness. By understanding the characteristics of the material, engineers can better select the appropriate grade for a specific application.
There are a few precautions to consider when working with A-286 stainless steel. The material should not be exposed to temperatures above 690C, as this can cause it to become brittle. It is also important not to weld the material above temperatures of 495C, as this can damage the material’s properties. Additionally, the material should not be exposed to halides such as chlorine and bromine, as these can cause corrosion.
In conclusion, Alloy 0Cr15Ni25MoTiAlVB (A-286) precipitation-hardened stainless steel is a type of stainless steel alloy that consists of a combination of metals that allow it to possess improved fatigue and fracture toughness properties. The material is often used in applications requiring high strength and good corrosion resistance. However, when working with this metal, precautions should be taken to ensure that the material is not exposed to temperatures above 690C, welding temperatures above 495C, or halides.
