Size, shape, volume fraction and distribution of embedded g/ phase in g phase has direct effect on strength of INCONEL alloy. Microstructure parameters of INCONEL phases are quantified from microstructure images using transmission electron microscopy (TEM). Different TEM sample preparation techniques were used to study INCONEL 738 alloy microstructure for transmission electron micros...

INCONEL alloy 783 was annealed and aged following the standard heat treatment procedure. One set of specimens was then isothermally exposed at 500 degrees C for 3000 h. Mechanical properties were measured at room temperature and 650 degrees C, and the results showed the prolonged exposure increased the strength and decreased elongation of alloy 783. The microstructures of as-produced and expose...

To date, KEK has developed cleaning techniques for superconducting niobium RF cavities. These include: electro-polishing (EP), buffered chemical polishing (BCP) barrel polishing (BP), high pressure rinsing (HPR), megasonic ]lot water rinsing, degassing water, ozonated water cleaning, waste water treatment, and so oil. In this paper, we present findings from electro-poloishing of cavities, which...

This paper presents the development of low cost Nano membrane fabrication system. The system is specially designed for anodic aluminum oxide membrane. This system is capable to perform the processes such as anodization and electro-polishing. The designed machine was successfully tested for ‘mild anodization’ (MA) for 48 hours and ‘hard anodization’ (HA) for 3 hours at constant 0C. The system is...

Problem statement: Single Point Diamond Turning (SPDT) is highly deterministic and versatile in producing various forms of precise optics. A typical example is the production of large offaxis aspheric mirrors and various infrared mirrors and mandrels. However, the fine periodical turning marks left in the surface critically limit its performance and they are difficult to be avoided for traditio...

Electro-chemical polishing is a process of improving micro smoothness, micro topology, and material brightness by anodic dissolving of the substrate in an electrolyte with an external source of electricity. The resulting surface improvements depend on the uniformity of the material microstructure, the lack of surface inclusions, and the consistency of the surface finish all over the target area...

The design of high pressure water jet based polishing equipment and its fabrication conducted in this study is reported herein, together with some preliminary test results for assessing its applicability for HMA surface polishing. This study also provides preliminary findings concerning the test variables, such as the rotational speed, the water jet pressure, the abrasive agent used, and the im...

Although computer controlled polishing (CCP) of aspheres and freeforms is one of the best understood state-of-the-art fab processes today, there are yet some unsolved issues: e.g. compared to bonnet polishing, fluid jet polishing is taking less iteration steps reaching the same form accuracy and ion beam figuring eventually is reaching much higher shape accuracies. This paper is a first move in...

We present a new finishing process that is capable of locally shaping and polishing optical surfaces of complex shapes. A fluid jet system is used to guide a premixed slurry at pressures less than 6 bars to the optical surface. We used a slurry comprising water and 10% #800 SiC abrasives (21.8 mum) to reduce the surface roughness of a BK7 sample from 350 to 25 nm rms and to vary the shape of a ...