Deep flaws in weldments of aluminum and titanium

Surface flawed specimens of 2219-T87 and 6Al-4V STA titanium weldments were tested to determine static failure modes, failure strength, and fatigue flaw growth characteristics. Thicknesses selected for this study were purposely set at values where, for most test conditions, abrupt instability of the flaw at fracture would not be expected. Static tests for the aluminum weldments were performed at room, LN2 and LH2 temperatures. Titanium static tests for tests were performed at room and LH2 temperatures. Results of the static tests were used to plot curves relating initial flaw size to leakage- or failure-stresses (i.e. "failure" locus curves). Cyclic tests, for both materials, were then performed at room temperature, using initial flaws only slightly below the previously established failure locus for typical proof stress levels. Cyclic testing was performed on pairs of specimens, one with and one without a simulated proof test cycle. Comparisons were made then to determine the value and effect of proof testing as affected by the various variables of proof and operating stress, flaw shape, material thickness, and alloy

Fracture characteristics of structural aerospace alloys containing deep surface flaws

Conditions controlling the growth and fracture of deep surface flaws in aerospace alloys were investigated. Static fracture tests were performed on 7075-T651 and 2219-T87 aluminum, and 6Ai-4V STA titanium . Cyclic flaw growth tests were performed on the two latter alloys, and sustain load tests were performed on the titanium alloy. Both the cyclic and the sustain load tests were performed with and without a prior proof overload cycle to investigate possible growth retardation effects. Variables included in all test series were thickness, flaw depth-to-thickness ratio, and flaw shape. Results were analyzed and compared with previously developed data to determine the limits of applicability of available modified linear elastic fracture solutions

Investigation of deep flaws in thin walled tanks

Growth of deep surface flaws in thin wall tanks of aluminum and titanium base metal

Law in the Electronic Brothel: How Postmodern Media Affect First Amendment Obscenity Doctrine

This Comment seeks to examine the implications of media ecology models for the past, present, and possible future of obscenity doctrine. Section II of this Comment applies the first model in examining the historical origins of obscenity doc- trine in light of media ecology. This analysis of history reveals a critical presupposition about the effects of media on human behavior

Law in the Electronic Brothel: How Postmodern Media Affect First Amendment Obscenity Doctrine

This Comment seeks to examine the implications of media ecology models for the past, present, and possible future of obscenity doctrine. Section II of this Comment applies the first model in examining the historical origins of obscenity doc- trine in light of media ecology. This analysis of history reveals a critical presupposition about the effects of media on human behavior

Investigation of crack growth threshold of Inconel 718 exposed to high pressure oxygen Final report 24 Apr. - 25 May 1970

Crack growth threshold investigation of Inconel 718 exposed to high pressure oxyge

Outpatient Injuries of the Hand

All hand injuries, regardless of superficiality, may result in crippling loss of function if treatment is inadequate or mishandled. The essential elements of diagnosis, examination, approach to therapy and after-care are constant. The major difference between an injury requiring hospitalization and one amenable to outpatient management is the extent of the trauma. This article reviews the major outpatient injuries with respect to method of management, choice of definitive procedure, and preservation of function