Niobium-based compositions and coatings, niobium oxides and their alloys applied by thermal spraying and their use as an anticorrosive

• US 20060127577A1
• Filed: 11/13/2002
• Published: 06/15/2006
• Est. Priority Date: 09/06/2002
• Status: Active Grant

• Current Assignee: Coppe/Ufrj-Coordenacao Dos Programas de POS Graduacao de Engenharia Da Universidade Federal Do Rio de Janeiro
• Original Assignee: Coppe/Ufrj-Coordenacao Dos Programas de POS Graduacao de Engenharia Da Universidade Federal Do Rio de Janeiro
• Inventors: Carvalho, Ladimir Jose, Goncalves Pereira, Antonio Carlos, Miranda, Luiz Roberto Martins
• Granted Patent: US 7,651,731 B2
• Time in Patent Office: Days
• US Class Current: 427/250
• CPC Class Codes: C22C 27/02 Alloys based on vanadium, niobium, or tantalum
• CPC Class Codes: C23C 4/02 Pretreatment of the material to be coated, e.g. for coating on selected surface areas
• CPC Class Codes: C23C 4/04 characterised by the coating material
• CPC Class Codes: C23C 4/08 containing only metal elements C23C4/073 takes precedence
• CPC Class Codes: C23C 4/11 Oxides

Abstract

The novelty proposed herein describes the application of niobium-based compositions and coatings, niobium oxides and their alloys capable of associations with other oxides and alloys by means of the thermal spraying technique for the purpose of an anticorrosive protection in highly corrosive environments, mainly those which present high temperatures, show presence of gases such as H₂S, SO₂, CO₂, as well as organic and inorganic acids, commonly found in industrial centers.

Claims

1. “

Niobium-Based Compositions and Coatings, Niobum Oxides and Their Alloys Applied by Thermal Spraying”

characterized by applying niobium, its oxides and alloys such as Ni—

Nb, Fe—

Nb, HNb, among others, obeying the following characteristics, boiling point up to a maximum of 2000°

C., density of 4.47 to 8.0 g/cm³, niobium oxide 99.4%, sulphur ppm at 10, Fe ppm at 229, Pb ppm at <

1 and granulometry of [−

180 to 45 μ

m] by thermal spraying.

2. “

Niobium-Based Compositions and Coatings, Niobium Oxides and Their Alloys Applied by Thermal Spraying”

according to claim 1, characterized by using, more specifically in case of an adherence pre-layer, the agglomerate of 40 Al-60 Nb with niobium oxide with a granulometry between −

180 to 45 μ

m.

3. “

Niobium-Based Compositions and Coatings, Niobium Oxides and Their Alloys Applied by Thermal Spraying”

, according to claim 1, characterized by obeying the following parameters for application of the niobium oxide and niobium alloys, oxygen pressure of 2.0 to 4.0 kg/cm³, acetylene pressure of 0.5 to 1.0 kg/cm², deposition rate regulation 5-15.

4. “

Use as an anticorrosive”

as described in Me preceding claim 1, characterized by using niobium and niobium alloys such as Ni—

Nb, Fe—

Nb, HNb among others, as an anticorrosive coating.

5. “

Niobium-Based Compositions and Coatings, Niobium Oxides and Their Alloys Applied by Thermal Spraying”

, according to claim 2, characterized by obeying the following parameters for application of the niobium oxide and niobium alloys, oxygen pressure of 2.0 to 4.0 kg/cm³, acetylene pressure of 0.5 to 1.0 kg/cm², deposition rate regulation 5-15.

6. “

Use as an anticorrosive”

as described in claim 2, characterized by using niobium and niobium alloys such as Ni—

Nb, Fe—

Nb, HNb among others, as an anticorrosive coating.

7. “

Use as an anticorrosive”

as described claim in 3, characterized by using niobium and niobium alloys such as Ni—

Nb, Fe—

Nb, HNb among others, as an anticorrosive coating.