Laser net shape manufacturing (LNSM) is a laser cladding/deposition based technology, which can fabricate and repair near-net-shape high-performance components directly from metal powders. Characterizing mechanical properties of the laser net shape manufactured components is prerequisite to the applications of LNSM in aircraft engine industrial productions. Nickelbased superalloys such as INCONEL 718 are the most commonly used metal materials in aircraft engine high-performance components. In this study, the laser deposition process is optimized through a set of designed experiments to reduce the porosity to less than 0.03 pct. It is found that the use of plasma rotating electrode processed (PREP) powder and a high energy input level greater than 80 J/mm are necessary conditions to minimize the porosity. Material microstructure and tensile properties of laser-deposited INCONEL 718 are studied and compared under heat treatment conditions of as deposited, direct aged, solution treatment and aging (STA), and full homogenization followed by STA. Tensile test results showed that the direct age heat treatment produces the highest tensile strength equivalent to the wrought material, which is followed by the STA-treated and the homogenization-treated tensile strengths, while the ductility exhibits the reverse trend. Finally, failure modes of the tensile specimens were analyzed with fractography.

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A national survey showed that nearly half of all major managed care organizations in the United States refuse to credential nurse practitioners as primary care providers. In nurse-managed health centers throughout the country, nurse practitioners provide primary care to underserved populations with similar outcomes to primary care physicians. Insurers' prohibitive credentialing and reimbursement policies reduce these centers' capacity for growth and, in turn, threaten the long-term sustainability of a key component of the health care safety net. Two years after conducting a national survey of insurers' credentialing and reimbursement policies regarding primary care nurse practitioners, researchers returned to the subject matter and found that many of the same financial barriers to nurse-managed health center sustainability still exist. Although some progress had been made since 2005, this progress did not appear to be attributable to regulatory changes or renewed enforcement of existing laws.

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