Quartz Glass and its Manufacturing Method

Abstract

A quartz glass with excellent thermal insulation and mechanical strength, and a method thereof, are provided. A quartz glass has a porosity of 0.5% or more, an average pore size of 8.0 μm or less, and an average pore roundness of 0.70 or more. Furthermore, a method for manufacturing a quartz glass includes: a preparation step of mixing 2 or more parts by mass of graphite powder with 100 parts by mass of amorphous silica powder to obtain a raw material powder; a forming step of forming the raw material powder to obtain a shaped body; and a sintering step of sintering the shaped body. In the method for manufacturing the quartz glass, the amorphous silica powder includes a first silica powder with an average particle size of 0.60 μm or more and 2.50 μm or less, and a second silica powder with an average particle size of 0.001 μm or more and 0.060 μm or less, and the graphite powder has an average particle size of 0.50 μm or more and 10.00 μm or less.