SU1247417A1 - Coolant for diamond machining of optical glasses - Google Patents

Description

I., 1

The invention relates to coolant lubricants (coolants) that can be used for diamond processing of optical glasses.

The aim of the invention is to improve the quality of the surface and process productivity by reducing the surface roughness and shortening the time of polishing optical glasses of the brands TF, BF, F TK, KF, etc., with a relative hardness of shredding lower than 0.7%. GOST 13659- 68,

The reaction of polyethylene-polyamine (NEP) and compounds with an activated double bond — acrylic acid or 2, 3 epoxy-1-propanol — proceeds with an exothermic effect in an aqueous solution and is completed upon subsequent heating to 80–100 ° C. for 3 hours. PEP MM 8 1 thousand,. .

The reaction is carried out as follows: To a solution of 43 g of PEPA MM 8-11 thousand in 50 MP ligO is added dropwise acrylic acid (AA) in the amount of 7-30 g (depending on the requirements of the synthesis). The reaction mixture is spontaneously heated to. At the end of the addition, the reaction mixture is hardened and quenched for another 3 hours at C, the qualitative synthesis reaction is completed and the reaction mixture does not contain more acrylic acid if no more than 70 mol of acid was added per NEP amino acid group

In a similar way, PEPA is synthesized with 2,3-epoxy 1-propanol.

Due to the presence of acidic properties in the molecules of the resulting product upon its adsorption on the glass surface, the migration of new alkali metals from the surface layer (acceleration) is enhanced and, thus, the magnitude of the negative surface charge on the glass increases. This increases the strength of the electrostatic bond of the proto-ni- olipane molecules of the polymer obtained with the glass surface.

The described effect causes an increase in the strength of the boundary film and thus an increase in the lubricating properties of the liquid and an improvement in the quality of the treated surface.

2

For testing, we took the composition of a known coolant,% by mass:

Polyethylenepolyamine

MM 100000.1

Water 99.9

Experiments on the ntyping method of priter carried out on the machine 9 SHP-50. We processed blocks of flat blanks from optical glass BF-16 as a typical representative of soft glass (hardness of grinding 0.51 Block diameter 70 mm original surface roughness Kg 0.4 μm, the rotation frequency of the machine spindle 1100 rpm, pressure on the tool 1 kg / cm, processing cycle 40 s Instrume; nt assembly, consists of 24 diamond tablets on a bronze bond of 6 cm СSM diamond 10/7 diamond, concentration in the instrument 6% feed rate CO L when circulating in a closed volume 3 l / min

Polishing of polished glass surfaces was carried out according to the method of free grinding with the use of polymers and resin polishing pad.

This table contains data on the effect of the quantitative composition of the polymer additive and its concentration in water on the surface roughness of the treated glass surface and the polishing time to remove the ruined j o layer. The resulting grinding performance for all test compositions is close and lies within 200-240 microns / min.

As can be seen from the table, the positive effect of the proposed composition of the coolant is reached j when the ratio of the initial components of the synthesis reaction is in the range of 1-10: 1, and the concentration of the polymer additive in water is 0.1-1% by weight, and the minimum roughness of the treated surface is 4: 1 ratio (PEPAGAK or 2 5 3-epoxy-1-propanol),

The lower limit: the ratio of the starting components (10: 1) is due to the fact that, with a lower content of acrylic acid, its amount: 1: and its effect does not significantly affect the performance characteristics of the coolant. and the upper limit provides the maximum possible, on the basis of the chemical properties of the reagents, the reaction coverage of all the original amino groups,

Practically reasonable range of polymer concentration values

3,124

additives can be defined as 0, OT-I wt.%. When its concentration is below 0.01%, the effect of the coolant becomes less noticeable compared to pure water. An increase in the concentration of more than 1.0% is impractical from economic considerations, since it does not give an increase in the positive effect of C07.

Compiled by T Salamova Editor M, Kelemesh Tehred V. Kadar Corrector. Shekmar

Order 4080/26 Circulation 482 Subscription

VNIISH State Committee of the USSR

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., d 4/5

Production and printing company, Uzhgorod, st. Project, 4

Table continuation

Claims (1)

LUBRICANT-COOLING LIQUID FOR DIAMOND PROCESSING OF OPTICAL GLASSES, containing water and a polymer additive based on polyethylene polyamine, characterized in that, in order to improve the quality of the polished surface, the liquid as a polymer additive contains the product of the interaction of polyethylene polyamine with acrylic acid or with 2,3 -1-propanol taken in a molar ratio of 1-10: 1 with the following content of components, wt.%: The product of the interaction of polyethylene polyamine with acrylic acid or 2,3-epoxy-1-propanol taken in a molar ratio of 1-10: 1 Water 0.01-1.0 99.0-99.99 SU ,, 1247417