Abstract: Friction stir weld tools configured to bond or laminate thin sheets. Friction stir weld tools have a first shoulder, a pin extending from a friction surface of the first shoulder, and a second shoulder. In some embodiments, the second shoulder is secured at least partially around the first shoulder and includes an engagement surface longitudinally recessed with respect to the friction surface of the first shoulder. In additional embodiments, the second shoulder is proximate the first shoulder and rotationally fixed. In yet additional embodiments, the pin has a diameter that is greater than the height of the pin and the second shoulder is secured at least partially around the first shoulder. Methods include manufacturing such friction stir weld tools. Methods include friction stir welding using such tools.

Abstract: A method of preparing a high purity metal nitride and/or oxide powder is provided, comprising: heating a metal salt and an organic fuel to an ignition temperature in a nitrogen-rich atmosphere, forming a first composition; and optionally heating the first composition to a heat treatment temperature, which heat treatment temperature is above the ignition temperature and below 1000° C., in a nitrogen-rich atmosphere until the metal nitride and/or oxide powder is formed.

Abstract: A method for making high purity, multiphasic calcium phosphate powders using an Auto-Ignition Combustion Synthesis (AICS) reaction of a calcium salt, a phosphate salt and a fuel is provided. In the method provided, energy released from the AICS reaction between the calcium salt, phosphate salt and fuel ignites at temperatures much lower than the actual phase transformation temperatures and reaches a high temperature rapidly enough for synthesis of the desired product to occur, without the requirement for coprecipitation, an external heat source for calcination and/or additional steps for removing undesired precursors from the desired final product.