Described are glass-forming molds made of a graphite mold body and a coating formed by atomic layer deposition, with the coating being made of alumina or a combination of alumina and yttria.

A method for producing a component with portions of a rare earth metal-doped quartz glass, an intermediate product containing voids and consisting of a SiO.sub.2 raw material doped with rare earth metal is introduced into a sinter mold the interior of which is bordered by a carbonaceous mold wall, and is melted therein into the component by gas pressure sintering at a maximum temperature above 1500 C. A shield is arranged between the mold wall and the intermediate product. In order to indicate a modified gas pressure sintering method that ensures the production of rare earth metal-doped quartz glass with reproducible properties, a bulk material of amorphous SiO.sub.2 particles with a layer thickness of at least 2 mm is used as the shield, the softening temperature thereof being at least 20 C. higher than the softening temperature of the doped SiO.sub.2 raw material, and the bulk material being gas-permeable at the beginning of the melting of the intermediate product, and the bulk material sintering during melting into an outer layer that is gas-tight to a pressure gas.

A mold for processing glass and a method for processing glass are disclosed. The mold is used for processing glass for processing a planar glass structure into a three-dimensional glass structure. The mold includes a lower mold part and an upper mold part. The lower mold part is made of material having a thermal expansion coefficient of approximately 510.sup.6Kapproximately 7.5810.sup.6K. The upper mold part is made of material having a thermal expansion coefficient of approximately 810.sup.6Kapproximately 2810.sup.6K. The upper mold part is capable of engaging with or separating from the lower mold part. When the upper mold part is engaged with the lower mold part, the upper mold part is engaged with the lower mold part cooperatively define a molding space for molding the three-dimensional glass structure.

An amorphous alloy contains Ni and Nb and has a composition including at least one of: a composition containing Nb with a content in the range of 35.6 atomic % to 75.1 atomic %, Ir with a content in the range of 7.2 atomic % to 52.3 atomic %, and Ni with a content in the range of 4.0 atomic % to 48.5 atomic %; a composition containing Nb with a content in the range of 19.6 atomic % to 80.9 atomic %, Re with a content in the range of 7.4 atomic % to 59.2 atomic %, and Ni with a content in the range of 4.1 atomic % to 56.9 atomic %; and a composition containing Nb with a content in the range of 7.5 atomic % to 52.9 atomic %, W with a content in the range of 16.4 atomic % to 47.0 atomic %, and Ni with a content in the range of 22.0 atomic % to 53.3 atomic %.

A mold for molding a glass product is provided. The mold includes a lower mold and an upper mold. The lower mold includes a lower pressing surface. The upper mold includes an upper pressing surface. The upper pressing surface includes a plurality of upper molding surfaces and an upper mold closing surface connecting the plurality of upper molding surfaces. The lower pressing surface includes a plurality of lower molding surfaces and a lower mold closing surface for connecting the plurality of lower molding surfaces. The upper mold closing surface and/or the lower mold closing surface include at least two mold closing regions sequentially arranged from center to outside. The at least two mold closing regions have surface roughnesses increasing from center to outside. The disclosure achieves the technical effect of even filling, synchronous demoulding, and reduced error between mold cavities.

A method for treating a mold includes grinding an outer metal surface of a mold body of the mold with a first material; lapping the outer metal surface after the grinding with a second material that is finer than the first material; and polishing the outer metal surface after the lapping to achieve an average surface roughness (R.sub.a) less than or equal to about 0.15 m and a waviness height (W.sub.a) less than or equal to about 100 nm. A mold for shaping glass-based material can include a mold body having an outer metal surface, wherein the outer metal surface has an average surface roughness (R.sub.a) less than or equal to about 0.15 m and a waviness height (W.sub.a) less than or equal to about 100 nm.

A method for further processing of a glass tube semi-finished product includes: providing the glass tube semi-finished product, along with tube-specific data for the glass tube semi-finished product; reading the tube-specific data for the glass tube semi-finished product; and further processing of the glass tube semi-finished product including a step of thermal forming carried out at least in sections. At least one process parameter during the further processing of the glass tube semi-finished product including the step of thermal forming carried out at least in sections is controlled as a function of the tube-specific data for the glass tube semi-finished product. In this way, the further processing can be matched more efficiently to the particular characteristics of a glass tube semi-finished product to be processed or a particular subsection thereof, and the relevant characteristics of the particular glass tube semi-finished product do not need to be measured again.

A method for treating a mold includes grinding an outer metal surface of a mold body of the mold with a first material; lapping the outer metal surface after the grinding with a second material that is finer than the first material; and polishing the outer metal surface after the lapping to achieve an average surface roughness (R.sub.a) less than or equal to about 0.15 m and a waviness height (W.sub.a) less than or equal to about 100 nm. A mold for shaping glass-based material can include a mold body having an outer metal surface, wherein the outer metal surface has an average surface roughness (R.sub.a) less than or equal to about 0.15 m and a waviness height (W.sub.a) less than or equal to about 100 nm.

Described are glass-forming molds made of a graphite mold body and a coating formed by atomic layer deposition, with the coating being made of alumina or a combination of alumina and yttria.

An optical element shaping mold set includes a first shaping mold and a second shaping mold that face each other; a tubular third shaping mold which is located around the first shaping mold and the second shaping mold and in which at least one of the first shaping mold and the second shaping mold slides, and heating, pressing and cooling are conducted with a shaping-target material accommodated between the first shaping mold and the second shaping mold, the third shaping mold has a slit formed on at least one of ends in a sliding direction of the at least one of the first shaping mold and the second shaping mold, and the third shaping mold has a linear expansion coefficient that is smaller than a linear expansion coefficient of the first shaping mold and smaller than a linear expansion coefficient of the second shaping mold.