ISSN:
1573-8256
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
,
Technology
Notes:
Conclusions 1. The quality of cutting instruments is determined not only by the strength characteristics of the material but also by its microstructure. Material for instruments with a fine cutting edge (microtome knives, eye scalpels, trephines, knives for commissurotomies, etc.) must be thoroughly checked for nonmetallic inclusions in accord with GOST 1778-62 and for carbide inhomogeneity and carbide network according to GOST 8233-56. For the indicated instruments all the aforesaid structural characteristics should not exceed the 1st scale point. 2. To increase the resistance of the cutting edge of instruments against chipping, the blank should be selected so that the steel fibers are directed across the cutting edge. 3. We can recommend steel 11Kh (ÉI603) for microtome knives. Knives of this steel must be heat-treated according to the following regimes. First heating in a compartment-type electric furnace at 400–500°, 6 min. Final heating in a salt bath (78% BaCl2 +22% NaCl) at 830°–860°, 6 min. Quenching in molten alkali (20% NaOH +80% KOH −6% water) at 150–180°, 6 min and thereafter in air. Tempering in a bath (55% KNO3 +45% NaNO2) at 180–200°, 3–4 h. Hardness RCH 60–62.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00557636
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