Author: SM. Graham
Publisher:
ISBN:
Category : Alloy 718
Languages : en
Pages : 14
Book Description
The fracture toughness and tensile properties of Alloy 718 were measured at quasi-static and dynamic loading rates for two different heat treatments and two product forms. Two different methods for conducting the dynamic tests were investigated; one involving interrupted tests and the other utilizing a single impact. The interrupted test method used multiple impacts with displacement limits to enable measurement of crack lengths at intermediate points. The normalization method was used to generate tearing resistance curves for the dynamic tests following the guidelines in ASTM Standard Test Method for measurement of Fracture Toughness (E 1820). The analysis pointed out the importance of obtaining a good measurement of load, displacement, and crack length at the point of maximum displacement (the anchor point). As the amount of ductile crack extension increased, the uncertainty in the plasticity function fit also increased. Methods to improve the fit were investigated, including the addition of anchor points from multiple tests, and use of a tangency point to estimate initiation. The resulting curves are compared to ascertain the variability obtained from nominally identical specimens, and to evaluate the effect of loading rate on the plasticity function. The normalization tearing resistance curves are compared with curves generated from the interrupted tests using compliance measurements during unloads to determine crack extension. Good agreement was obtained between the two methods of measuring tearing resistance, thereby validating the normalization analysis. The tests showed that multiple impacts drive down the tearing resistance, which may be significant in applications where a dynamic event causes load fluctuation.
Application of the Normalization Method to Dynamic Fracture Toughness Testing of Alloy 718
Fatigue and Fracture Mechanics
Author: Richard Edward Link
Publisher:
ISBN:
Category : Technology & Engineering
Languages : en
Pages : 544
Book Description
Publisher:
ISBN:
Category : Technology & Engineering
Languages : en
Pages : 544
Book Description
Evaluation of Dynamic Fracture Toughness Using the Normalization Method
Author: G. Carcagno
Publisher:
ISBN:
Category : Dynamic fracture testing
Languages : en
Pages : 17
Book Description
This paper presents a simple technique to determine dynamic J-R curves from a single, precracked Charpy-type specimen by means of an instrumented Charpy testing machine. This technique is based on the normalization method proposed originally by Landes and Herrera. This method eliminates the need for crack length monitoring that makes it particularly suitable under dynamic loading conditions.
Publisher:
ISBN:
Category : Dynamic fracture testing
Languages : en
Pages : 17
Book Description
This paper presents a simple technique to determine dynamic J-R curves from a single, precracked Charpy-type specimen by means of an instrumented Charpy testing machine. This technique is based on the normalization method proposed originally by Landes and Herrera. This method eliminates the need for crack length monitoring that makes it particularly suitable under dynamic loading conditions.
Fracture Toughness Testing and Its Applications
Fracture Toughness Testing and Its Applications
Author: ASTM Committee E-24 Staff
Publisher: ASTM International
ISBN: 9780803101050
Category : Technology & Engineering
Languages : en
Pages : 430
Book Description
Publisher: ASTM International
ISBN: 9780803101050
Category : Technology & Engineering
Languages : en
Pages : 430
Book Description
Application of Normalization Method to Fracture Toughness Testing of Welds with Pronounced Strength Heterogeneity
Metals Abstracts
J Integer Fracture Toughness Testing of Alloy 718
Compliance Ratio Method of Estimating Crack Length in Dynamic Fracture Toughness Tests
Author: WJ. Wright
Publisher:
ISBN:
Category : Crack length measurement
Languages : en
Pages : 19
Book Description
Crack extension during fracture toughness tests of ferritic structural steels cannot be determined from measurements of unloading compliance or electric potential change when the specimen is dynamically loaded. Measurements of crack extension in fracture toughness tests are also very difficult when the test temperature is high or the test environment is aggressive. To circumvent this limitation, researchers for years have been developing key curve and normalization function methods to estimate crack extension in standard elastic-plastic fracture toughness test geometries.
Publisher:
ISBN:
Category : Crack length measurement
Languages : en
Pages : 19
Book Description
Crack extension during fracture toughness tests of ferritic structural steels cannot be determined from measurements of unloading compliance or electric potential change when the specimen is dynamically loaded. Measurements of crack extension in fracture toughness tests are also very difficult when the test temperature is high or the test environment is aggressive. To circumvent this limitation, researchers for years have been developing key curve and normalization function methods to estimate crack extension in standard elastic-plastic fracture toughness test geometries.