CN104944743A

CN104944743A - Forming method of far-infrared glass globe lens blank

Info

Publication number: CN104944743A
Application number: CN201410111657.5A
Authority: CN
Inventors: 郭作超
Original assignee: Individual
Current assignee: Individual
Priority date: 2014-03-25
Filing date: 2014-03-25
Publication date: 2015-09-30

Abstract

The invention relates to a processing method and hot pressing device of a far-infrared glass globe lens blank. The method comprises the following steps: closing an upper mold and a lower mold which are previously arranged into a hemispherical recess array at high temperature, and forming the far-infrared glass disk under nitrogen-charged conditions, thereby implementing mass processing of the far-infrared glass globe lens blanks.

Description

The forming method of far infrared glass globe lens blank

Technical field

The present invention relates to a kind of forming method of far infrared glass globe lens blank, particularly relate to a kind of high-temperature thermo-compression formation method of processing chalcogenide glass globe lens blank, greatly can improve the utilization ratio during materials processing of chalcogenide glass.

Background technology

In recent years, due to rare earth element, especially the price of germanium (Ge) rises, and makes originally much to use germanium single crystal brings into use advantage of lower cost far infrared glass material as an alternative as the application of infra-red material.Far infrared glass, namely chalcogenide glass (chalcogenide glass) is with sulfide, and selenide and stibnide are the glass of main component.Chalcogenide glass can be saturating for the light of mid and far infrared wave band, is a kind of important far-infrared material.On the other hand, germanium single crystal, cannot be hot-forming as crystalline material, can only become non-spherical lens by single-point diamond machined into high costs.And chalcogenide glass can carry out hot-pressing processing as the material of vitreous state.

It is the chalcogenide glass globe lens at high temperature precise compression molding adopting surface finish that now general far infrared glass non-spherical lens is produced, thus directly die mould goes out non-spherical lens.Chalcogenide glass globe lens diameter for precise compression molding is 3mm to 15mm.Need of production melting in the vitreosil Glass tubing of circle of chalcogenide glass, so the glass raw material of producing is all cylindric, diameter is the processing mode of the current globe lens of 50mm to 200mm.: first cut out the cubes more bigger than globe lens from the chalcogenide glass starting material of bulk, then cubes is ground balling-up base, finally ball base is refined, be polished to globe lens.The utilization ratio of such chalcogenide glass is from initial glass raw material to final globe lens less than 20%, and waste is serious, and the cost of such infra-red material can account for more than 50% of final lens cost.

Summary of the invention

The present invention devises a set of heat pressing forming device, adopts a kind of hot-press method that the chalcogenide glass disk cut in advance is directly pressed into multiple ball base.And then to be refined by ball base and to be polished to globe lens.The utilization ratio of such chalcogenide glass material can bring up to about 80% by original less than 20%, significantly reduces the cost of Infrared Lens.

Accompanying drawing explanation

Fig. 1 is the sectional view of heat pressing forming device.

wherein Reference numeral

1 is mold;

2 is bed die;

3 is upper fixture;

4 is lower clamp;

5 is resistive heater;

6 is quartz glass cover;

7 is chalcogenide glass disk;

8 is heat radiation air drain.

Embodiment

Be described in more detail invention below, similar mark represents identical or like.But in order to better understanding, the parts shown in accompanying drawing schematically show, they are drawn in proportion, namely the parts of this accompanying drawing do not represent full-size(d), and these full-size(d)s are all known for those of ordinary skills, therefore without the need to being described in detail.

With reference to the sectional view of figure 1 heat pressing forming device.Mold 1 non-die mould surface by center to edge radial distribution heat radiation air drain 8.Structure and the mold 1 of bed die 2 are completely the same.Mold 1 and bed die 2 are all manufactured by high temperature stainless steel, and wherein process hemispheric die cavity array to the die mould face of chalcogenide glass by single-point diamond numerically-controlled machine, the roughness Ra of die cavity inwall is less than 30nm, mainly for the ease of withdrawing pattern.The diameter range of upper/lower die 1,2 is between 100 to 150mm.The disc surfaces laminating of mold 1 and upper fixture 3.The axle of upper fixture 3 is hollow, and the space of assembling rear axis with mold 1 forms path with heat radiation air drain 9.Bed die 2 is above-mentioned consistent with being assemblied in of lower clamp 4.The material of upper lower clamp 2,4 is identical with the material of upper/lower die 1,2, is all high temperature stainless steel, mainly for making thermal expansivity at high temperature consistent.

The diameter of chalcogenide glass disk 8 depends on the size of glass ingot, but can not exceed the diameter of upper/lower die.The thickness of chalcogenide glass disk 7 will be slightly less than the diameter of ball base after final die mould, is generally 90% of ball base diameter.Quartz glass cover 6 is circular hollow silica tube, and external diametrical extent is between 180mm to 200mm, and thickness is between 3 ~ 5mm.Quartz glass cover closed set on the Up/down base of die mould machine, and can be opened by improving the height of upper bed-plate.Resistive heater 5 is uniformly distributed and is wrapped in quartz glass cover periphery, its altogether heating power between 5kw to 8kw.

Lower mask body introduces die mould process.First open the quartz glass cover 6 of sealing, place chalcogenide glass disk in bed die 2 central position.Closed quartz glass cover 6, the shaft clearance and the air drain that dispels the heat that then begin through lower clamp 3,4 and upper/lower die 1,2 vacuumize, until air pressure inside reaches 0.1MPA.At this moment resistive heater 5 is started working, infrared penetration quartz glass cover radiation between the transition temperature Tg value 100 degree to 120 degree that the temperature of upper/lower die is reached higher than chalcogenide glass.Beginning die mould after upper/lower die 1,2 is fully heated evenly, during die mould, mold 1 and upper fixture 3 move down and apply pressure to chalcogenide glass disk 8, and pressure is between 20kg to 50kg, until upper/lower die 1,2 closes.At this moment chalcogenide glass softens completely and has very viscid mobility, and chalcogenide glass can be full of whole spherical die cavity under the effect of the pressure.

When the temperature of upper/lower die 1,2 drops to lower than chalcogenide glass transition temperature Tg value 120 degree, nitrogen displacement can be strengthened with fast cooling.When upper/lower die 1,2 cool to room temperature, lifting mold 1 and upper fixture 3.Due to volumetric shrinkage after chalcogenide glass cooling, its ball base can be peeled off with mold 2, and stays in the die cavity of bed die 1.

Claims

1. the working method of a far infrared glass ball globe lens blank and heat pressing forming device, adopt the upper/lower die of semispherical indentations array in advance at high temperature airtight and by far infrared glass disk die mould under the condition of inflated with nitrogen, thus batch machining become far infrared glass globe lens blank.

2. heat pressing forming device according to claim 1, is characterized in that, the non-die mould surface of upper/lower die by center to edge radial distribution heat radiation air drain; The die mould surface of upper/lower die goes out semisphere die cavity array by single-point diamond lathe in machining, and the diameter of hemisphere is consistent with ball base that finally will be shaping, and its diameter range is between 3 ~ 15m.

3. according to the heat pressing forming device in the claims described in any one, it is characterized in that, vacuumized with the air drain that dispels the heat by the shaft clearance of upper lower clamp and upper/lower die before hot-forming.

4. according to the heat pressing forming device in the claims described in any one, it is characterized in that, the infrared radiation produced by resistive heater before hot-forming heats upper/lower die and chalcogenide glass disk through quartz glass cover.

5. according to the heat pressing forming device in the claims described in any one, it is characterized in that, resistive heater is closed after mould is closed, and input nitrogen to the axial slits of bed die and lower clamp, the heat radiation air drain of nitrogen flow through molds from bottom to top, extracting out with the axial slits of upper fixture by mold, by controlling the gas transmission speed of nitrogen to control the rate of temperature fall of upper/lower die.

6. according to the heat pressing forming device in the claims described in any one, it is characterized in that, beginning die mould after upper/lower die and chalcogenide glass disk are fully heated evenly, during die mould, mold and upper fixture move down and apply pressure to chalcogenide glass disk, until upper/lower die closes.