Abstract: A blade assembly is connected to a robot arm for transmission of semiconductor chips and includes a blade, a top cover, a bottom cover, and two pivot units each including a pivot arm, a first bearing, and a second bearing. Thus, the positioning flange of the mounting ring of the pivot arm is sandwiched between the first bearing and the second bearing and the inner washer is sandwiched between the inner ring of the first bearing and the inner ring of the second bearing, thereby preventing the first bearing from pressing and jamming the second bearing due to a pressing action of the urging cap, so that the pivot arm is pivotable smoothly and stably.

Abstract: Damage-tolerant, continuous fiber ceramic matrix composites are fabricated to fill the space between the fibers with a powder. The powder particles are heat treated to form a porous framework without shrinkage, which is then strengthened with an inorganic synthesized from a precursor in solution. High particle packing densities is achieved within the fiber preform using a small particle-to-fiber diameter ratio. Filling the interstices with a powder increases the composite density and also limits the size of the crack-like voids within the matrix. The ceramic matrix composite (CMC) has mechanical characteristics similar to those found in wood. It is also affordable and inherently oxidation resistant. The composite is characterized by a heterogeneous distribution of fibers within a porous matrix having a homogeneous, fine porosity. A residual stress from thermal expansion mismatch of the matrix and fibers is created in the composite. The illustrated embodiment uses Al.sub.2 O.sub.