Accession Number:

AD0871155

Title:

Investigation to Determine the Feasibility of Detecting Impending Metal Fatigue Failure through Use of an Inductive Sensing Device

Descriptive Note:

Final technical rept.

Corporate Author:

MECHANICAL TECHNOLOGY INC LATHAM NY

Personal Author(s):

• Moross, George G.

Report Date:

1970-02-01

Pagination or Media Count:

129.0

Abstract:

The program is concerned with the evaluation and development of a sensing system to detect surface and near-surface flaws in material, specifically to detect early fatigue damage. This system shows great promise in that a signal is detected at a significant time before failure, and the amplitude of the signal increases with further damage. Samples have been fatigue-cycled up to 5,000,000 cycles, and signals were observed as early as 38 of fatigue life, average results showing signals between 70-80. These studies were performed using aluminum, steel, and Inconel, and the results show essentially the same sensitivity of these materials. Intensive metallographic and microanalytic studies were performed in order to define the particular phenomenon responsible for the signal. Micro-cracks definitely proved to be responsible for the signal, and thus the sensitivity of the system was evaluated.

Descriptors:

• *METALS
• *NONDESTRUCTIVE TESTING
• ALUMINUM
• CRACKS
• FATIGUE(MECHANICS)
• INDUCTANCE
• NICKEL ALLOYS
• STEEL

Subject Categories:

• Fabrication Metallurgy
• Test Facilities, Equipment and Methods

Distribution Statement:

APPROVED FOR PUBLIC RELEASE