JPS5811796A - Heat protective heat resistant alloy structure and coating of surface of heat resistant alloy - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to thermally protective nickel-based and cobalt-based alloys such as high temperature alloys for surfaces of turbine blades, vanes, combustors and transition components used at high temperatures.

Prior art □ The operating temperature of the combustion gas used in the turbine is approximately 1093
℃ (-000''F) or above, many commercially available metals melt. As a result, engine design engineers have difficulty manufacturing turbine blades, vanes, combustor and transition components. In addition, to ensure that turbine blades and blade components operate effectively in high-temperature environments, blade components, particularly turbine blades, are typically coated with metal-based overlay coatings and outer overlays. It is covered by a coat or insulation layer.

By using a ceramic coating as a heat insulating layer, a heat insulating and corrosion resistant layer is formed on the surface of air-cooled metal parts. Such ceramic coatings improve turbine performance and reduce power generation costs in simple recovery-combination cycles, but the increased power generation efficiency and improved power generation costs associated with increased turbine inlet temperatures and the introduction of ceramic coatings. The greatest benefit in terms of 14 I/Ii merge cycles occurs. One of the biggest breakthroughs in increasing power generation efficiency and reducing power generation costs is through the use of ceramic coatings, which lower the turbine inlet temperature by 10 to 3 degrees Celsius (-00 degrees Celsius).
0"F) to / J 04g'(:(here 00"P
) to 9 is produced by increasing the temperature to 1314° C. (J l o “F ).Furthermore, in a given fuel process, substituting residual fuel can significantly reduce the cost of power generation for various cycle types.

Due to the significant performance improvements and fuel flexibility afforded by the use of ceramic coatings, plasma sprayed Ni0rAJY coatings of approximately 3 mils thick and approximately 0,3 t. ■(
It has been proposed to use a ZrO, . However, as a result of the test, Zr
O2/co'Y, O, plasma spray coatings are stable in clean combusted gas atmospheres, but do not contain sodium, sulfur, vanadium-magnesium (magnesium is a low quality fuel containing vanadium for the purpose of forming magnesium vanadate). In a combustion environment containing impurities (fuel additives added to the fuel), severe cracking and cracking was shown to occur even during a test period as short as 50 hours.

In addition, it has been proposed to use a composite calcium silicate (0&*810 a )/'Ni 0rAIY coating system, which is much more durable than composite coating systems based on zirconium oxide. Pine 〇, J burner rig test (mach O, 3bu
When a fuel containing sodium or vanadium impurities and a relatively low sulfur content is used in the rnθr rig test), the composite Z rO*・l
/Ni0rm IY coating with 1 hour cycle 6
It becomes unusable after 0 times, while composite Oa, 8104/N
The i0rAJY coating was found to last much longer. Furthermore, Z rOt・I Y
The z Os/M i Orm AY coating is unusable after 370 1-hour cycles, while the composite ○a
The 8104/NiOrm IY coating was found to last even longer. These tests show that the composite Oa 28104/Ni OrAjY coating system was tested in an atmospheric burner rig test (burner rig test).
Although it has been shown to have greater durability than composite zirconium oxide based coating systems in I/C, #1 is hardly satisfactory for practical turbine hard protection.

Real # by burning heavy petroleum fuel! Pressurized flow tests under hypothetical pressure, temperature, and contamination conditions of gas turbines used in industrial applications revealed that Ca, B104/Ni0rAJY specimens had a one-hour cycle cycle time that was far shorter than the expected useful life for the intended applications. After treatment, extensive spalling occurred on the coated surface. Post-test inspections have shown that Oa, SiO4 is chemically unstable in combustion environments containing vanadium, magnesium, and sulfur, which are often present in normal use.

A disadvantage of prior art thermal barrier coating systems, including adhesive coatings and overcoats, is that they limit the utility of turbine components such as vanes, turbine blades, combustors, and transition components.

The present invention relates to a heat-insulating alloy coating structure comprising an adhesive coating layer and a ternary silicate lamic thermal barrier coating layer applied on the metal adhesive coating layer.

The present invention further provides a surface coating consisting essentially of Ni0rAJY or OaOlMgO and S1
0. It also relates to a method of coating a surface of a nickel-based or cobalt-based alloy, the surface of which is coated with a ceramic thermal barrier coating layer consisting essentially of a ternary silicate formed from the present invention.

Thus, a coating system is provided to obviate the disadvantages of the heat-resistant coatings mentioned above.

The thermal barrier coating system includes an adhesive coating layer containing MOrAJY (where M is nickel or cobalt) and an adhesive coating layer containing Oak, MgO and 810. and a thermal barrier coating layer of ternary silicate. Ternary silicates are chemically more stable than Ca, 8104 in combustion gases and other environments containing vanadium-magnesium and sulfur. The ternary silicates that we have found to be most compatible with the above adhesive coating layer as having the highest coefficients of thermal expansion are OaO.MgO-8iO, and JCao.
-MgO・-810.

When applying a predetermined coating layer to a base material, MOr Mba (
An adhesive coating layer containing Mt (nickel or cobalt) is first applied to @l, followed by coating the adhesive coating layer and then coating the lR surface with a thermal barrier coating layer consisting of a ternary silicate. Coating system (double-1) Coating systems include plasma spraying, sputtering, and OVD.
(chemical vapor deposition), PVD or other suitable vapor deposition techniques may be applied.

The base metal of the turbine components, such as vanes, turbine blades, combustor and transition components, is a nickel refractory single tone metal or a cobalt refractory base metal. The coating layer has a low thermal conductivity and therefore provides a thermal insulation layer between the hot combustion gases and air-cooled metal parts such as combustor or turbine blades and engines, power generation turbine vanes or other air/liquid cooled components. used for. Thereby, the gas temperature can be increased, and this gas temperature increase j (0 which improves operating efficiency and reduces power generation costs), for example, the turbine inlet temperature is 109
It can be increased from 3°C (-000ν) to 1314°C (λpoo'P). “Fuel costs can be significantly reduced because residual fuel can be used instead of high quality fuel for a variety of operating conditions.

For example, adhesive coating layers of Ni0rAiY may be applied to metal substrates by plasma spraying, coating, slurry spraying, and sintering methods; such coating methods are described in prior art patents, such as U.S. Pat. ! f l
J, j J O No., same j, A 4. Ot No. 1 and Ot.
,? j 4t, No. 903, etc., and the others are well known in the i industry, so there is no need to describe them here.

However, it is important that the adhesive coating method selected forms a dense adhesive coating layer. The thermal barrier overcoat layer containing the ternary silicate can be applied to the adhesive coating layer using arc plasma or flame spray methods or other known application methods. The thickness of the adhesive coating layer can vary widely, but is preferably about 0.
/λ? ■(1 mil) thick. Similarly, the thickness of the heat insulating coating layer can be changed at any time, but it is preferably θ, 31 (
tS mill) It is moderately thick. The thickness of the coating layer may be varied to any degree to achieve the desired temperature drop across the thermal barrier coating layer. The ternary silicates found to be particularly useful are Cab, MgO and S10.
consisting of OaO-MgO-8iO, and J OaO
-MgO・CoS10. is suitable.

The applied coating temperature can be varied and is used to suit the particular application method chosen.

Each component of the coating system according to the invention can be prepared by conventional techniques.

Claims (1)

[Scope of Claims] l A base material that is a nickel heat-resistant base alloy or a nickel heat-resistant base alloy, a metal adhesive coating layer applied on the base material, and a ceramic heat-insulating coating layer applied on the metal adhesive coating layer. A heat-protecting, heat-resistant alloy structure comprising: a ceramic heat-insulating coating layer comprising a ternary silicate comprising OaOlMgO and B10. Thermal protection heat-resistant alloy structure according to claim 1.J The ceramic heat-insulating coating layer is OaO, MgO,
The heat-stable, heat-resistant alloy structure according to claim 1, which is EliO.倶 Ceramic heat insulation coating layer is 30aO・MgO
・-〇10. A heat-retaining and heat-resistant alloy structure according to claim 1. A heat-protecting, heat-resistant alloy structure according to any one of claims 7 to 7, wherein the metal adhesive coating layer is an alloy containing chromium, aluminum, and yttrium and nickel or cobalt. 4. The heat-protecting heat-resistant alloy structure according to any one of claims 1 to 5, wherein the base material is a nickel heat-resistant base alloy or a cobalt heat-resistant base alloy. The 75 Tsukel refractory base alloy or cobalt refractory base alloy surface is coated with a metal adhesive coating layer consisting essentially of MICr IY or OoOr IY, and then the # surface is coated with a layer of metal adhesive coating consisting essentially of MICr IY or 0OOr IY, and then the # surface is coated with a ternary silicate consisting essentially of O&Q, MgO and 5102. A method for coating the surface of a nickel heat-resistant base alloy or a cobalt heat-resistant base alloy, the method comprising coating the surface of a nickel heat-resistant base alloy or a cobalt heat-resistant base alloy with a ceramic heat-insulating coating layer comprising: The ceramic insulation coating layer is OaO, MgO,
S10. A method of coating a heat-resistant alloy surface according to claim 7, comprising: Responsibility: The thermal insulation coating layer of the ceramic construction is made of joao/MgO.
-1810. A method for coating the surface of a heat-resistant alloy according to claim 7, comprising: A heat-resistant alloy according to claim 1, wherein the surface of the heat-resistant alloy base material to be coated is a nickel heat-resistant base alloy or a cobalt heat-resistant base alloy. Surface coating method.