ABRASIVE FOR JET CUTTING

Abstract

An abrasive for jet cutting including particles of a stainless steel is provided, the stainless steel includes a microstructure, the microstructure including at least martensite, in a range of ≥20 wt. % to ≤100 wt. %, austenite in a range of ≥0 wt % to ≤50 wt %, and chromium carbide, chromium nitride and/or mixtures thereof, together in a range of ≥0 wt % to ≤45 wt % based on the microstructure, the proportions being selected such that together they amount to ≤100 wt % based on the microstructure. The abrasives for jet cutting exhibit particularly good lifetime and recyclability. Also provided is a suspension for jet cutting including at least the proposed abrasive for jet cutting and a suspending agent, as well as the use of the abrasive for jet cutting for cutting a workpiece.

Claims

1. An abrasive for jet cutting comprising particles of a stainless steel, the stainless steel consisting of a microstructure, the microstructure comprising at least: martensite, particularly in a range of ≥20 wt % to ≤100 wt %, austensite in a range of ≥0 wt. % to ≤50 wt. %; and chromium carbide, chromium nitride and/or mixtures thereof, together in a range of ≥0 wt % to ≤45 wt %, based on the microstructure, the proportions being selected such that they together amount to ≤100 wt. % based on the microstructure.

2. The abrasive for jet cutting according to claim 1, wherein the microstructure comprises chromium carbide, chromium nitride and/or mixtures thereof together in a range of ≥3 wt % to ≤35 wt % based on the microstructure, ≥10 wt % to ≤30 wt %, in particular ≥24 wt % to ≤28 wt %.

3. The abrasive for jet cutting according to claim 1, wherein the microstructure comprises austenite in a range of ≥5 wt % to ≤47 wt % based on the microstructure, ≥15 wt % to ≤40 wt %, in particular ≥25 wt % to ≤35 wt %.

4. The abrasive for jet cutting according to claim 1, wherein the stainless steel is made of an alloy, comprising: chromium in a range of ≥10 wt % to ≤35 wt %, molybdenum in a range of ≥0 wt % to ≤3 wt %, nickel in a range of ≥0 wt % to ≤1 wt %, carbon in a range of ≥0 wt % to ≤2.5 wt %, nitrogen in a range of ≥0 wt % to ≤2.5 wt %, trace elements in a range of ≥0 wt. % to ≤1 wt. %, and balance iron, based on the alloy, the alloy comprising carbon and nitrogen together in a range of ≥0.2 wt % to ≤2.5 wt % based on the alloy.

5. The abrasive for jet cutting according to claim 4, wherein the alloy comprises carbon and nitrogen together in a range of ≥0.6 wt % to ≤2.5 wt % based on the alloy, ≥0.8 wt % to ≤2.3 wt %, more ≥1.2 wt % to ≤2.1 wt %, in particular ≥1.8 wt % to ≤2 wt %.

6. The abrasive for jet cutting according to claim 4, wherein the alloy comprises chromium in a range of ≥15 wt % to ≤33 wt % based on the alloy, ≥20 wt % to ≤31 wt %, in particular ≥25 wt % to ≤30 wt %.

7. The abrasive for jet cutting according to claim 1, wherein the stainless steel particles have an equivalent diameter D.sub.90 in a range of ≥0.01 mm to ≤1 mm, ≥0.05 mm to ≤0.4 mm, in particular ≥0.09 mm to ≤0.315 mm, alternatively ≥0.01 mm to ≤0.5 mm, in particular ≥0.01 mm to ≤0.2 mm.

8. The abrasive for jet cutting according to claim 1, wherein the stainless-steel particles have a hardness in a range from ≥600 HV 0.2 to ≤1000 HV 0.2, from ≥700 HV 0.2 to ≤900 HV 0.2, in particular from ≥780 HV 0.2 to ≤830 HV 0.2.

9. The abrasive for jet cutting according to claim 1, wherein the particles are selected from shot, wire grain, grit, and mixtures thereof, wherein the particles are grit.

10. A suspension for jet cutting, comprising at least one abrasive for jet cutting according to claim 1 and a suspending agent, water.

11. Use of an abrasive for jet cutting according to claim 1 for cutting a workpiece.

Description

BRIEF DESCRIPTION

[0146] Some of the embodiments will be described in detail, with reference to the following figures, wherein like designations denote like members, wherein:

[0147] FIG. 1 shows the sieve distribution in wt % versus the number of cycles of the life test of an abrasive according to Example 2 in the range from 0 to 20 cycles;

[0148] FIG. 2 shows the sieve distribution in wt. % versus the number of cycles of the life test of an abrasive according to the comparative example; and

[0149] FIG. 3 shows the sieve distribution in wt % versus the number of cycles of the life test of an abrasive according to Example 2 in the range from 0 to 40 cycles.

DETAILED DESCRIPTION

[0150] FIGS. 1 to 3 show the results of the lifetime test for example 2 and the comparative example. For example 2, the corresponding weight fractions in % of the sieve fractions are shown as histograms for every 5 cycles. For the comparative example, the corresponding weight fractions in % of the sieve fractions were given for the first 3 cycles. The mesh sizes of the sieves used for fractioning during sieving are given in mm. Furthermore, logarithmic curves have been fitted to the measured data for the most prominent fractions and are shown as dashed lines.

[0151] Example 2 and the comparative example showed as new grain the sieve fraction with 0.21 mm mesh size as the largest fraction with more than 60 wt. %.

[0152] It can be seen from FIG. 1 that the fraction from 0.21 mm mesh size of the abrasive according to Example 2 hardly decreases and even after 20 cycles still accounts for about 55 wt. % of the screening fractions.

[0153] The comparable lifetime test for garnet according to the comparative example, shown in FIG. 2, showed that after only one cycle the fraction of 0.21 mm mesh size had already dropped to below 35% by weight. After 3 cycles, this fraction accounted for only slightly more than 10% by weight, which is why this abrasive could no longer be used after only 3 cycles.

[0154] FIG. 3 shows an extended lifetime test for the abrasive according to example 2. Even after 40 cycles, the fraction of 0.21 mm mesh size still accounts for the largest proportion and the abrasive can still be used accordingly.

[0155] As a result, the abrasives according to embodiments of the invention show significantly improved lifetime and recyclability compared to known abrasives.

[0156] Although the present invention has been disclosed in the form of preferred embodiments and variations thereon, it will be understood that numerous additional modifications and variations could be made thereto without departing from the scope of the invention.

[0157] For the sake of clarity, it is to be understood that the use of “a” or “an” throughout this application does not exclude a plurality, and “comprising” does not exclude other steps or elements. The mention of a “unit” or a “module” does not preclude the use of more than one unit or module.