Electrical discharge machining process and dielectric fluid useful therein

Claim 2

The process of claim 2 wherein said conductivity additive consists of a mixture of 2-5 parts by weight each of said chromium salt component and said alkaline earth metal salt component.

Claim 3

The process of claim 2 wherein said composition contains 0.02-0.25 percent by weight of said conductivity additive.

Claim 4

The process of claim 1 wherein said base oil is selected from the group consisting of substantially saturated aliphatic or alicyclic hydrocarbon compounds, esters, or mixtures thereof.

Claim 5

The process of claim 5 wherein said esters are alkyl esters of monocyclic aromatic carboxylic acids.

Claim 6

The process of claim 6 wherein said base oil is a mixture of kerosene and at least one C5-C15 alkyl ester of a monocyclic aromatic dicarboxylic acid having zero- two noncarboxylate substituents of one-four carbon atoms each on the benzene ring.

Claim 7

The process of claim 7 wherein said ester is dioctyl phthalate.

Claim 8

The process of claim 5 wherein said conductivity additive consists essentially of 2-5 parts each by weight of (1) a mixture of chromium salts of mono- and dialkyl salicylic acids with each alkyl substituent containing 12-20 carbon atoms; and (2) a calcium di(C8-C12 alkyl) sulfosuccinate.

Claim 9

The process of claim 9 wherein said composition contains 0.01-1.2 percent by weight of said conductivity additive.

Claim 10

The process of claim 10 wherein said composition contains 0.02-0.25 percent by weight of said conductivity additive.

Claim 11

A composition useful as an electrical discharge machining fluid which consists essentially of 90-99 parts by weight of a base fluid consisting of a mixture of kerosene and dioctyl phthalate in a volumetric ratio of 60-95 parts of kerosene to 40-5 parts of dioctyl phthalate, and 0.003-2.5 parts by weight of a conductivity additive consisting of a mixture of a chromium salt component and an alkaline earth metal salt component, wherein each of said components is present as 1-10 parts by weight of said additive, and wherein said chromium salt component comprises at least one chromium salt of an alkyl salicylic acid containing one or two alkyl substituents each of fRom eight-22 carbon atoms, and said alkaline earth metal salt component comprises at least one alkaline earth metal salt of a di(C4-C14 alkyl) sulfosuccinate.

Claim 12

The composition of claim 12 wherein said chromium salt compontne comprises at least one chromium salt of an alkyl salicylic acid containing one or two alkyl substituents of from 12-20 carbon atoms.

Claim 13

The composition of claim 13 wherein said alkyl substituents are of from 14-18 carbon atoms.

Claim 14

The composition of claim 12 wherein said alkaline earth metal salt component comprises a calcium salt of a di(C4-C14 alkyl) sulfosuccinate.

Claim 15

The composition of claim 15 wherein said calcium salt is a calcium salt of a di(C8-C12 alkyl) sulfosuccinate.

Claim 16

The composition of claim 16 wherein said calcium salt is calcium didecyl sulfosuccinate.

Claim 17

The composition of claim 12 wherein said base oil consists of 80-95 parts by volume of kerosene and 20-5 parts by volume of dioctyl phthalate.