KRASSIMIR GRIGOROV MARCHEV
Pilots at Patricia Rd, North Sudbury, MA
License number
Massachusetts A3941988
Issued Date
Oct 2015
Expiration Date
Oct 2017
Category
Airmen
Type
Authorized Aircraft Instructor
Address
Address
9 Patricia Rd, North Sudbury, MA 01776
Professional information
Method Of Plasma Nitriding Of Alloys Via Nitrogen Charging
US Patent:
8349093, Jan 8, 2013
Filed:
Jun 8, 2009
Appl. No.:
12/479904
Inventors:
Clark VanTine Cooper - Glastonbury CT, US
Krassimir G. Marchev - Sudbury MA, US
Bill C. Giessen - Cambridge MA, US
Krassimir G. Marchev - Sudbury MA, US
Bill C. Giessen - Cambridge MA, US
Assignee:
Sikorsky Aircraft Corporation - Stratford CT
International Classification:
C23C 8/24
US Classification:
148317, 148212, 428610
Abstract:
A nitrided metal includes a metal core with a first microstructure and a nitrogen-containing solid solution region on the metal core. The nitrogen-containing solid solution region is free of nitride compounds and includes a second microstructure which is equivalent to the first microstructure. The first microstructure and the second microstructure are a tetragonal crystal structure.
Process Of Forming A Razor Blade
US Patent:
7966909, Jun 28, 2011
Filed:
Jul 25, 2007
Appl. No.:
11/881288
Inventors:
John Madeira - Assonet MA, US
Arutiun Papken Ehiasarian - Sheffield, GB
Papken Ehiasar Hovsepian - Sheffield, GB
Krassimir Grigorov Marchev - Sudbury MA, US
Neville Sonnenberg - Newton MA, US
Arutiun Papken Ehiasarian - Sheffield, GB
Papken Ehiasar Hovsepian - Sheffield, GB
Krassimir Grigorov Marchev - Sudbury MA, US
Neville Sonnenberg - Newton MA, US
Assignee:
The Gillette Company - Boston MA
International Classification:
B21K 11/00, B26B 21/54
US Classification:
761041, 3034653, 3034654
Abstract:
The present invention relates to a process for forming a razor blade. The process includes the steps of: a) providing a substrate, b) forming a wedge-shaped sharpened edge on the substrate that has an included angle of less than thirty degrees and a tip radius of less than 1,000 angstroms, c) placing the substrate in a vacuum chamber, d) placing a first solid target in the vacuum chamber, e) providing a gas to be ionized in the vacuum chamber, and f) generating ions from the first solid target by applying a negative voltage to the first solid target in pulses, the ions forming a thin film coating on the wedge-shaped sharpened edge on the substrate.
Method For Processing Alloys Via Plasma (Ion) Nitriding
US Patent:
7695573, Apr 13, 2010
Filed:
Sep 9, 2004
Appl. No.:
10/937100
Inventors:
Clark VanTine Cooper - Glastonbury CT, US
Krassimir G. Marchev - Sudbury MA, US
Bill C. Giessen - Cambridge MA, US
Raymond C. Benn - Madison CT, US
Edward H. Bittner - Madison CT, US
Harsh Vinayak - Meriden CT, US
Krassimir G. Marchev - Sudbury MA, US
Bill C. Giessen - Cambridge MA, US
Raymond C. Benn - Madison CT, US
Edward H. Bittner - Madison CT, US
Harsh Vinayak - Meriden CT, US
Assignee:
Sikorsky Aircraft Corporation - Stratford CT
International Classification:
C23C 8/24, C23C 8/48, C23C 22/00
US Classification:
148238, 148317
Abstract:
A surface processing method and power transmission component includes transforming a surface region of a metal alloy into a hardened surface region at a temperature that is less than a heat treating temperature of the metal alloy. The metal alloy includes about 11. 1 wt % Ni, about 13. 4 wt % Co, about 3. 0 wt % Cr, about 0. 2 wt % C, and about 1. 2 wt % Mo which reacts with the C to form a metal carbide precipitate of the form MC. The surface processing temperature, vacuum pressure, precursor gas flow and ratio, and time of processing are controlled to provide a desirable hardened surface region having a gradual transition in nitrogen concentration.
Method Of Plasma Nitriding Of Metals Via Nitrogen Charging
US Patent:
7556699, Jul 7, 2009
Filed:
Jun 17, 2004
Appl. No.:
10/870489
Inventors:
Clark VanTine Cooper - Glastonbury CT, US
Krassimir G. Marchev - Sudbury MA, US
Bill C. Giessen - Cambridge MA, US
Krassimir G. Marchev - Sudbury MA, US
Bill C. Giessen - Cambridge MA, US
International Classification:
C23C 8/36, C23C 8/24
US Classification:
148222, 148238
Abstract:
A method of nitriding a metal includes transforming a surface region of a generally nitrogen-free metal into a nitrogen-containing solid solution surface region. A first heating process heats the surface region at a first temperature in the presence of a nitrogen gas partial pressure to form a nitrogen-charged surface portion on the surface region. A second heating process heats the surface region and nitrogen-charged surface portion at a second temperature for a predetermined time to interstitially diffuse nitrogen from the nitrogen-charged surface portion a depth into the surface region. Coincident with the second heating process, an ionized inert or reducing gas removes the nitrogen-charged surface portion. The resulting nitrogen-containing solid solution surface region has a gradual transition in nitrogen concentration.
Thin Film Coating Of Blades
US Patent:
2011020, Sep 1, 2011
Filed:
May 12, 2011
Appl. No.:
13/105958
Inventors:
John Madeira - Assonet MA, US
Arutiun Papken Ehiasarian - Sheffield, GB
Papken Ehiasar Hovsepian - Sheffield, GB
Krassimir Grigorov Marchev - Sudbury MA, US
Neville Sonnenberg - Newton MA, US
Arutiun Papken Ehiasarian - Sheffield, GB
Papken Ehiasar Hovsepian - Sheffield, GB
Krassimir Grigorov Marchev - Sudbury MA, US
Neville Sonnenberg - Newton MA, US
International Classification:
C23C 14/34
US Classification:
20419216
Abstract:
The present invention relates to a process for forming a razor blade. The process includes the steps of: a) providing a substrate, b) forming a wedge-shaped sharpened edge on the substrate that has an included angle of less than thirty degrees and a tip radius of less than 1,000 angstroms, c) placing the substrate in a vacuum chamber, d) placing a first solid target in the vacuum chamber, e) providing a gas to be ionized in the vacuum chamber, and f) generating ions from the first solid target by applying a negative voltage to the first solid target in pulses, the ions forming a thin film coating on the wedge-shaped sharpened edge on the substrate.
Razors And Razor Cartridges
US Patent:
2010001, Jan 21, 2010
Filed:
Jul 16, 2008
Appl. No.:
12/174093
Inventors:
Joseph Allan DePuydt - Scituate MA, US
Steve S. Hahn - Wellesley MA, US
John Madeira - Assonet MA, US
Krassimir Grigorov Marchev - Sudbury MA, US
Kenneth James Skrobis - Maynard MA, US
Neville Sonnenberg - Newton MA, US
Steve S. Hahn - Wellesley MA, US
John Madeira - Assonet MA, US
Krassimir Grigorov Marchev - Sudbury MA, US
Kenneth James Skrobis - Maynard MA, US
Neville Sonnenberg - Newton MA, US
International Classification:
B26B 21/00
US Classification:
30 50
Abstract:
Razors cartridges including a guard, a cap, and at least two blades with parallel sharpened edges located between the guard and cap are provided. A first blade defines a blade edge nearest the guard and a second blade defines a blade edge nearest the cap. The first blade has a cutter force less than the cutter force of the second blade.
Strengthened Razor Blade
US Patent:
2010029, Dec 2, 2010
Filed:
May 26, 2009
Appl. No.:
12/471551
Inventors:
Krassimir Grigorov Marchev - Sudbury MA, US
John Madeira - Assoner MA, US
John Madeira - Assoner MA, US
International Classification:
B26B 21/56, B26B 21/58, B21K 11/00
US Classification:
30 48, 3034653, 761041
Abstract:
A razor blade including a substrate with a cutting edge, the substrate includes a mixed nitride-substrate interregion disposed at or beneath a surface of the substrate, the mixed nitride-substrate interregion being substantially free of a compound layer.