BRC10604291F1 - HOMOGENEOUS IRON BASED ALLOY WITH GOOD RESISTANCE TO CORROSION AND WEAR - Google Patents

Description

“HOMOGENOUS IRON-BASED AUSTENIC ALLOY WITH GOOD RESISTANCE TO CORROSION AND WEAR” [0001] Certificate of Invention PI0604291-0, filed on 10/13/2006 BACKGROUND OF THE INVENTION

This invention relates to corrosion-resistant and wear-resistant iron-based austenitic alloys which have excellent resistance to sulfuric acid and which are superior to high-grade and high-chromium and high-grade iron-based alloys. high carbon, for many applications where both wear and corrosion by sulfuric acid occur simultaneously. This invention further relates to such corrosion resistant alloys usable to produce valve seat inserts used in internal combustion engines with an exhaust gas recirculation (EGR) system.

Internal combustion engines equipped with EGR systems require inlet valve seat insert materials with excellent corrosion resistance due to the formation of sulfuric acid in the inlet insert area when sulfur oxide comes from of diesel fuel after combustion meets the humidity of the incoming air. The sulfur content of diesel fuel seems relatively low; however, sulfuric acid concentration will likely increase with engine run time, as the exhaust gas combustion deposits accumulated around the inner wall area of an intake insert will absorb more sulfuric acid. Severe corrosion can occur on inlet valve seat inserts made of M2 tool steel as the amount of acid at high concentration is sufficient. Stellite® 3 cobalt-based alloy (Stellite is a registered trademark of Deloro Stellite Holdings Company) has excellent corrosion resistance and good wear resistance under the working conditions of the diesel engine intake valve, and therefore this alloy Cobalt is usually the choice as an intake valve insert material to ensure the service life of the valve train on diesel engines equipped with an EGR device.

Traditionally, modified tool steel M2 and Silichrome XB are two common material choices for producing diesel engine intake valve seat inserts. In broad ranges, modified M2 tool steel comprises 1.2-1.5 wt% carbon, 0.3-0.5 wt% silicon, 03-0.6 wt% manganese, 6.07 , 0 wt% molybdenum, 3.5-4.3 wt% chromium, 5.0-6.0 wt% tungsten, up to 1.0 wt% nickel and the rest being iron. Modified Silichrome XB is believed to contain 1.3-1.8 wt% carbon, 1.9-2.6 wt% silicon, 0.2-0.6 wt% manganese, 19, 0-21.0 wt% chromium, 1.0-1.6 wt% nickel and the rest being iron. Another common iron-based alloy for inlet valve seat inserts contains 1.8-2.3 wt% carbon, 1.8-2.1 wt% silicon, 0.2-0.6 wt% by weight manganese, 2.0-2.5 wt.% molybdenum, 33.0-35.0 wt.% chromium, up to 1.0 wt.% nickel and the rest being substantially iron. There are also several high chromium type iron based alloys available to produce intake valve seat inserts.

US 6,916,444 discloses an iron-based alloy containing a large amount of residual austenite for inlet valve seat insert material. US 6,436,338 describes a corrosion resistant iron based alloy for diesel engine valve seat insert applications. U.S. Patent No. 6,866,816 describes an austenitic iron-based alloy with good corrosion resistance. However, the more severe corrosion conditions of some high sulfur fuel engines with high humidity require materials with much better corrosion resistance than the iron alloys identified above.

High chromium and high carbon nickel based alloys typically do not exhibit good wear resistance under inlet valve seat insert working conditions due to a lack of combustion deposits and an insufficient amount of oxides. metal valves typically found in exhaust valve applications, which helps protect the exhaust valve seat insert from direct metal-to-metal wear. Eatonite® 2 (Eatonite is a registered trademark of Eaton Corporation) is an example of nickel based alloys used to produce exhaust valve seat inserts believed to contain 2.0-2.8% by weight of carbon, up to 1.0 wt% silicon, 27.0-31.0 wt% chrome, 14.0-16.0 wt% tungsten, up to 8.0 wt% iron and the rest being essentially nickel. Several similar nickel-based alloys with added iron and / or cobalt are also available for exhaust valve seat inserts. U.S. Patent 6,200,688 describes high silicon and high iron type nickel based alloys used as material for valve seat inserts. These nickel based alloys may possibly be used in EGR engines only when the intake valve insert wear rate is moderate.

Wear resistant cobalt based alloys are another type of materials used in the industry and the most commonly used are Stellite® 3 and Tribaloy® T-400 (Tribaloy is a registered trademark of Deloro Stellite Corporation) for more demand. Based on the teachings of US patents 3,257,178 and 3,410,732, it is believed that Tribaloy® T400 contains 2.0-2.6 wt% silicon, 7.5-8.5 wt% 26.5-29.5 wt% molybdenum, up to 0.08 wt% carbon, up to 1.50 wt% nickel, up to 1.5 wt% iron and the rest being essentially cobalt. Stellite® 3 is further believed to contain 2.3-2.7 wt% carbon, 11.0-14.0 wt% tungsten, 29.0-32.0 wt% chrome, up to 3 , 0 wt.% Nickel, up to 3.0 wt.% Iron and the rest being cobalt. The above cobalt-based alloys have excellent resistance to both corrosion and wear. However, the cost of these cobalt-based alloys only allows these alloys to be used in limited applications.

Iron-based valve austenitic alloys or valve lining alloys can also be classified in the same material group. US 4,122,817 describes an iron-based austenitic alloy with good wear resistance, corrosion resistance and PbO oxidation. U.S. Patent 4,929,419 describes heat, corrosion and wear resistant austenitic steel for internal combustion exhaust valves. However, even with all of the above, there is still a need for a corrosion-resistant iron-based alloy with good wear resistance, particularly an austenitic iron-based alloy with excellent corrosion resistance that meets the specific demand from the harshest. corrosion conditions generated on a diesel engine equipped with EGR systems.

BRIEF SUMMARY OF THE INVENTION

A new iron-based austenitic alloy has thus been developed which has corrosion resistance close to that of Stellite 3 under the condition of hot dilute sulfuric acid in a cyclic corrosion test at high temperatures.

Such an alloy has sufficient wear resistance to meet the requirements of engines equipped with EGR systems. The cost of the alloy object of the present invention is significantly lower than the cost of cobalt-based alloys such as Stellite® and Tribaloy® [ In one aspect, the present invention is an alloy of the following composition: Preferably the alloy will contain at least 50% by weight of iron. In another aspect of the invention, the metal components are produced from the alloy, such as by casting, or by the powder metallurgy method, molding from a powder and sintering. In addition, the alloy may be used for hard coating of components as a protective coating by wire or powder methods.

DETAILED DESCRIPTION OF THE INVENTION

The present invention will be described below and its different aspects will be defined in detail. Each aspect thus defined may be combined with other aspects unless otherwise indicated. In particular, each feature indicated as being preferred or advantageous may be combined with any other feature indicated as being preferred or advantageous. All percentages given herein are percentages by weight unless otherwise specified.

Numerous experiments have been performed in order to develop the alloys with the desired attributes. Alloys with excellent corrosion resistance under acid-immersion type static tests may have poor performance under cyclic heating corrosion, because of the different corrosion behaviors at high temperatures and the possible influence of oxidation on the corrosion process. High temperature cyclic corrosion testing provides a tool for studying corrosion behavior under the influence of oxidation under high temperature conditions. According to studies conducted in the development of the alloys of the invention, numerous alloying elements can affect the hardness, corrosion and wear resistance of the alloy. It is preferred to have a minimum hardness of 34 HRC in order to obtain good wear resistance of the inventive austenitic alloy. However, the austenitic alloy may become too brittle when the hardness of the alloy exceeds 54 HRC due to the formation of intermetallic compounds as a sigma phase of excessive amount of alloying elements. It is relatively easier to achieve a great deal of corrosion resistance at higher chrome and low nickel contents under low carbon content. In stainless steels such as AISI 300 series, carbon content is controlled to a minimum to reduce both carbon retained chromium content and carbide / matrix limits for improved corrosion resistance. Unfortunately, valve seat insert alloys almost always have much higher carbon content than corrosion resistant stainless steels, because a large volumetric fraction of alloy carbides is required for higher hardness and better wear resistance of the alloys. wear resistant using alloy carbides as primary hard phases, which is contrary to the requirement of high corrosion resistance. US 6,666,816 describes an austenitic alloy employing low to medium and high molybdenum chromium content. For good corrosion resistance and good wear resistance, an example within the scope of US 6,866,816 shows an alloy containing about 1.6 wt% carbon. For even higher corrosion resistance, a much higher chromium content is used in the present inventive alloy, together with a higher carbon content, to form more alloy carbides to compensate for the hardness reduction. and wear resistance due to the higher chromium content. Unlike US patent 6,666,816, where high levels of refractory alloying elements such as molybdenum and tungsten are used for higher corrosion resistance and higher hardness, refractory alloying contents may cause brittleness problems. in the present inventive alloys when these refractory alloying elements combine with chromium, silicon and other alloying elements to form harmful intermetallic phases. Another different path needs to be tested in order to increase the hardness and wear resistance of this inventive high chrome type alloy. Through many experimental tests, it has been found that the hardness of the preferred inventive alloy can achieve the hardness of the alloy described in US 6,666,816.

EXAMPLES

The chemical compositions of all samples are given in Table 1. These alloy samples were prepared in a 27 kg industrial frequency induction furnace by means of a conventional atmosphere melting process. Samples subjected to corrosion, hardness, wear, heat tearing and shrinkage testing were cast into shell molds.

Comparative alloy samples in Table 1 have compositions or properties outside the scope of this invention. There are also three commercial Stellite 3, M2 and Silichrome XB alloys and four samples made according to the teachings of some of the above mentioned patents, listed in Table 1 as comparative alloys.

Ring samples with 45 mm outside diameter, 32 mm inside diameter and 5 mm thickness were used as hardness samples. Hardness values for all samples were obtained using a Rockwell C hardness tester. Such ring samples were also used to examine shrink defects and heat tear defects of the sample alloys. All samples made with the alloys of the invention can produce low scrap ring ring castings having 45mm outside diameter, 32mm inside diameter and 5mm thickness.

[0018] A high temperature cyclic corrosion tester has been built to simulate the corrosion of sulfuric acid at high temperature. The new corrosion tester provides a better method of corrosion measurement than traditional traditional static immersion corrosion testing, as both oxidation and high temperature are also important factors contributing to the corrosion process in the insert working environment. inlet valve.

The high temperature cyclic corrosion testing apparatus is composed of a heating coil, a pneumatic cylinder, a specimen with its support, a control unit and an acid solution container. First, the pneumatic cylinder lifts the sample into the heating coil to heat the specimen. The sample is held within the coil for about 22 seconds so that the temperature of the specimen reaches about 149 ° C. The pneumatic cylinder then moves the heated sample down into the sulfuric acid solution container and the cycle continues to repeat, taking about 24 seconds per cycle. All acidic solution left in the sample is vaporized when the sample is heated inside the heating coil. Therefore, both corrosion and oxidation occur in this process, which is closer to the actual insert corrosion of EGR-equipped engines than the static acid dip test. Corrosion also occurs when the treated specimen is pushed into the sulfuric acid solution container. The test time was one hour. The sample dimensions were 6.35 mm in diameter and 31.75 mm in length. About 12.7 mm in sample length were immersed into the solution. Sulfuric acid solutions of 0.25 vol%, 0.50 vol% and 1.0 vol% were used for each sample alloy. A precision balance was used to measure the weight of each sample before and after the test. The accuracy of the scale was 0.0001 grams. Corrosion weight loss is the weight difference of a sample before and after this corrosion test. The lower the corrosion weight loss, the higher the corrosion resistance of an alloy sample. Such results are expected to be analogous to actual corrosion testing on engines with EGR systems. The results of the corrosion tests are shown in Table 2 below, where the results of sample alloy # 4 are repeated several times for ease of comparison. The composition of the alloys of the present invention yield a corrosion weight loss preferably less than 5.0 mg, 10.0 mg and 18 mg in 0.25, 0.5 and 1.0 vol% sulfuric acid solutions. in the high temperature cyclic corrosion tester respectively.

A high temperature disc pin wear tester was used to measure the slip wear resistance of the alloys. Although current wear mechanisms are much more complex than disc pin wear processes, the test measures slip wear under high temperature conditions, which is the common wear mode that occurs in valve seat inserts. An Eatonite® 6 valve alloy pin specimen was constructed having approximate dimensions of 6.35 mm in diameter and 25.4 mm in length. Eatonite® 6 was used as a pin alloy because it is the most commonly used valve surface alloy. Discs with sample alloys were constructed, each disc having approximate dimensions of 50.8 mm in diameter and 12.5 mm in thickness. The tests were performed at a temperature of about 260 ° C according to ASTM G99-90. The tests were performed on samples after simple heat treatment of the disks at temperatures of about 649Ό for two hours. Each disc was rotated at a speed of 0.13 m / s for a total sliding distance of 255 m. Weight loss was measured on disc samples after each test using a 0.1 mg scale. Preferably, the sample will have a wear loss of less than 450 mg when tested under the above conditions. As a reference to wear tests, discs made of M2, Silichrome XB and Stellite® 3 tool steel were also constructed and tested. The results of the wear test are shown in Table 3 below.

[0021] An X-ray examination test was used to determine internal casting defects in parts cast with the sample alloy. Eight pieces of ring specimens of the same dimensions were selected for verification of casting defects such as internal contractions and heat tearing. Results are shown in Table 4 below. Contraction and tearing tendencies under heat were rated from 1 to 5, with 1 being the worst rating and 5 being the best rating. A rating of 3 was considered acceptable for both types of defects. Although relatively low, the number of samples showed good indications for most alloy defects in heat shrinkage and tearing.

Table 1. Hardness and Chemical Composition of the Alloy (% w) Table 2. Corrosion Test Results (Weight Loss; mg) Table 3. Wear Test Results Table 4, Heat Tear and Shrink Test Results [0022 ] Samples 1-7, 7A and 7B contain carbon contents of 1.2 to 3.2 wt% with silicon 1.0 wt%, chrome 18.00 wt%, tungsten 7.0 wt%, nickel 16 wt%, vanadium 1.0 wt%, niobium 1.0 wt%, aluminum 0.04 wt%, copper 1.5 wt%, the balance or balance to 100% iron with other impurities associated with the casting of raw materials. Wear test results indicate that wear resistance increases with carbon content increasing from 1.2 to 3.2% by weight. The hardness variation in such sample alloys follows the same trend as the wear resistance. High carbon sample alloys have better wear resistance than M2 tool steel and Silichrome XB.

The carbon content of the inventive alloy must be at least 1.8 or higher in order to obtain the required hardness, because the hardness of alloys with 1.2 and 1.4 wt% carbon samples is only 29.0 and 30.4 HRC, respectively, and the weight loss of these two comparative sample alloys is 560.1 mg and 481.6 mg, respectively. The corrosion resistance of alloys of samples containing different carbon contents appears to remain virtually constant and also meets corrosion resistance standards. Low carbon comparative sample alloys 1 and 2 have better corrosion resistance at low sulfuric acid concentrations. However, such low carbon comparative sample alloys do not have sufficient wear resistance. In addition, as shown in the data in Table 4, the contraction defect in comparative sample 1 and 2 alloys is acceptable, but the tear test rating in these two low carbon comparative sample 1 and 2 alloys is unacceptable. On the other hand, when the alloy carbon content ranges from 3.0 wt% to 3.2 wt%, the tear test rating is acceptable. Therefore, the carbon content to obtain good hardness and casting properties, the carbon content should be in the range of about 1.8 to about 3.5% by weight, preferably in the range of about 2 to about 3 wt.% And most preferably in the range of from about 2.3 to about 2.7 wt.% Samples 8 through 14 contain chromium from 10.0 to 22.0 wt.%. carbon 2.5 wt%, silicon 1.0 wt%, tungsten 7.0 wt%, nickel 16.0 wt%, vanadium 1.0 wt%, niobium 1.0 wt%, aluminum 0 , 04% by weight, covers 1.5% by weight and the rest being iron, with other impurities associated with the melting of the raw materials. These samples having different chromium contents illustrate the effects of chromium on hardness and corrosion and wear resistance. Low chromium alloys provide lower corrosion resistance, while higher chromium alloys have lower hardness and less wear resistance. Therefore, the chromium content of the inventive alloy must be within the range of about 12 to about 24% by weight, preferably in the range of about 14 to about 22% by weight and more preferably in the range of about 16 to about 24%. about 20% by weight, for the balance of good corrosion resistance and adequate wear resistance. Although comparative sample 15 has adequate hardness, it has too much wear rate.

Samples 6 and 16 to 20 contain tungsten and / or molybdenum in a range from 2.0 to 15.0 wt%, with 2.5 wt% carbon, 1.0-2.0 wt% silicon , chrome 18.0 wt%, nickel 16.0-25.0 wt%, vanadium 1.0-2.0 wt%, niobium 1.0 wt%, aluminum 0.04 wt%, copper 1.5% by weight and the rest is iron with other impurities associated with foundry casting. Increasing tungsten and molybdenum content has little effect on hardness and corrosion in the range tested. In fact, a high tungsten or molybdenum content causes a decrease in wear resistance. It is not necessary to use high molybdenum and / or tungsten content for better corrosion or higher hardness of the inventive alloy. Similar to high-speed steels, the addition of molybdenum or tungsten improves the hot hardness of the inventive alloy, which is important for the design application view, since inlet insert working temperatures can reach 371oC. The combined molybdenum and tungsten contents are defined to be within 2.0 to 16.0 wt%, preferably 3.0 to 15.0 wt%. In some alloys tungsten will be between about 3.0 and about 7.0% by weight and may not contain molybdenum. In other alloys, the combination of molybdenum and tungsten will be between 10.0 and 16.0 wt%, with molybdenum preferably 12.0 to 15.0 wt% and no tungsten. Too much tungsten or molybdenum causes brittleness problems for inventive alloy castings.

Samples 6, 21,22 and 23 contain a nickel content in the range of 12.0 to 25.0 wt%, with 2.5 wt% carbon, 1.0 wt% silicon, chromium 18 , 0 wt%, tungsten 7.0 wt%, vanadium 1.0 wt%, niobium 1.0 wt%, aluminum 0.04 wt%, copper 1.5 wt% and the rest being iron , with other impurities associated with casting of raw materials. Nickel makes a positive contribution to the corrosion resistance of the alloy. First, there is a minimum amount of nickel required to form stable austenite in the alloy. Second, higher nickel contents generally improve the corrosion resistance of the alloy at all acid concentrations tested. However, the improvement is at the expense of lower hardness and therefore less wear resistance. Therefore, the nickel content needs to be in the range from about 12 to about 25% by weight, preferably in the range of about 13 to about 20% by weight, more preferably in the range of about 14 to about 25%. 18% by weight.

Samples 5 and 24 contain vanadium of 1.0 to 3.0 wt%, with carbon 2.2 wt%, silicon 1.0 wt%, chromium 18.0 wt%, tungsten 7, 0 wt%, niobium 1.0 wt%, aluminum 0.04 wt%, copper 1.5 wt% and the rest being iron, with other impurities associated with the melting of the raw materials. Vanadium and niobium are strong MC carbide forming alloying elements. A small addition of vanadium and niobium helps improve the corrosion resistance of the alloy at low acid concentrations. A high addition of vanadium is also beneficial for reducing shrinkage and hot tear defects. However, too much vanadium or niobium decreases the hardness and wear resistance of the alloy. From the results of wear, corrosion, shrinkage and hot tear testing, the vanadium content should be in the range of about 0.02 to about 3% by weight. Similarly, the niobium content should be in the range of about 0.02 to about 3 wt%. The vanadium and niobium contents combined should be in the range from about 0.05 to about 4 wt%, preferably in the range from about 1 to about 3.5 wt% and more preferably in the range of about 1 0.5 to about 2.5% by weight.

Samples 6 and 24A, 25 and 25A contain 1.0 to 4.0 wt% silicon, with 2.5 wt% carbon, 18.0 wt% chrome, 7.0 wt% tungsten nickel 16 wt%, vanadium 1.0 wt%, niobium 1.0 wt%, aluminum 0.04 wt%, copper 1.5 wt% and the rest being iron with other impurities associated with the smelter of raw materials. Silicon has deoxidizing and desulfurizing effects during the alloy casting process. Silicon also has the effect of improving flowability. However, the main reasons for using silicon in the inventive alloy is that silicon can also improve corrosion and wear resistance of the alloys. Increasing the silicon content from 1.0 to 4.0% by weight improves the corrosion resistance of the inventive alloy. If the Si content is less than 0.5%, the effects on wear and corrosion are not achieved. If the Si content is more than 4.0% by weight, especially in the high carbon austenitic alloy, the excessive amount of silicon makes the alloy too brittle. A higher amount of silicon also decreases the hardness of the inventive alloy. Therefore, the silicon content needs to be within the range of about 0.5 to about 4 wt%, preferably in the range of about 0.5 to about 2.5 wt%, and more preferably in the range of about 0.5 to about 4% by weight. 0.5 to about 1.5 wt%.

The addition of copper increases the corrosion resistance of the alloy significantly. However, too much copper decreases the wear resistance of the alloy. Therefore, the amount of copper in the alloy must be within the range of about 0.05 to about 3% by weight, preferably in the range of about 0.5 to about 2.5% by weight, more preferably in the range. from about 1.0 to about 2.0% by weight.

Manganese also has deoxidizing and desulfurizing effects on molten metals. However, manganese can deteriorate corrosion resistance if its content is too high. Therefore, the manganese range needs to be less than about 1.5 wt%, preferably less than about H wt%, more preferably in the range of about 0.2 to about 0.6 wt%.

A small amount of aluminum and optionally titanium is added in the inventive alloys for degassing and precipitation hardening purposes. The amount of aluminum should be in the range from about 0.01 to about 0.2% by weight, preferably in the range from about 0.02 to about 0.1% by weight, more preferably in the range of about 0.03 and about 0.06% by weight. The range for titanium is from about zero to about 1% by weight, preferably in the range from about 0.01 to about 0.5% by weight, more preferably from about 0.02% by weight to about 1%. 0.06% by weight. When these elements are added and the alloys heat treated, wear resistance will be improved.

The corrosion and hardness test results for M2 tool steel, Stellite® 3, Tribaloy® T400, Silichrome XB and alloys within the ranges specified in US patents 6,666,816; US 6,916,444; US 6,436,338; US 3,257,178 and US 4,122,817 are also provided in Table 1 and Table 2. It is obvious that many inventive samples have much better resistance to corrosion and wear than M2 tool steel and Silichrome XB. Some samples are even close to the Stellite® 3 and Tribaloy® T400 cobalt-based alloys for corrosion resistance. However, these samples are much less expensive than cobalt-based alloys.

It should be appreciated that the alloys of the present invention are capable of being incorporated in the form of a variety of embodiments, only some of which have been illustrated and described. The invention may be embodied in other forms without departing from its spirit or essential characteristics. It should be appreciated that the addition of some other ingredients, process steps, materials or components not specifically included will have an adverse impact on the present invention. The best mode of the invention may therefore exclude ingredients, process steps, materials or components other than those listed above for inclusion or use in the invention. However, the described embodiments are considered in all respects to be illustrative and non-limiting only and the scope of the invention is therefore indicated by the appended claims rather than the preceding description. All changes that fall within the meaning and equivalence range of the claims are to be encompassed within its scope.

Claims (20)

1. Homogeneous iron-based austenitic alloy with good corrosion and wear resistance, Certificate of Addition of Invention PI0604291-0, filed 13/10/2006 according to claim 1 of application PI0604291-0, characterized by It comprises: (a) 1,8 to 3,5% by weight of carbon; b) 12 to 24 wt% chromium; c) 0.5 to 4% by weight of silicon; d) 12 to 25 wt% nickel; e) 2 to 16% by weight of combined tungsten and molybdenum; f) 0.05 to 4% by weight of combined niobium and vanadium; g) 0 to 1% by weight of titanium; h) 0.01 to 0.2 wt% aluminum; (i) 0.05 to 3% by weight of copper; j) less than 1.5% by weight of manganese; (k) at least 40% by weight of iron. Part for an internal combustion engine, characterized in that it consists of the alloy as defined in claim 1. Workpiece according to Claim 2, characterized in that the workpiece is cast by casting the alloy or hard coated with the alloy in the form of both wire and powder. Part according to claim 2, characterized in that it is shaped by a powder sintering metallurgy method. Alloy according to claim 1, characterized in that the amount of carbon is between 2.3 and 2.7% by weight. Alloy according to claim 1, characterized in that the amount of chromium is between 16 and 20% by weight. Alloy according to claim 1, characterized in that the amount of silicon is between 0.5 and 1.5% by weight. Alloy according to claim 1, characterized in that the amount of tungsten and molybdenum combined is between 3 and 7% by weight. Alloy according to claim 1, characterized in that the amount of nickel is between 14 and 18% by weight. Alloy according to claim 1, characterized in that the amount of niobium and vanadium combined is between 1.5 and 2.5% by weight. Alloy according to claim 1, characterized in that the amount of titanium is between 0.02 and 0.06% by weight. Alloy according to claim 1, characterized in that the amount of aluminum is between 0.03 and 0.06% by weight. Alloy according to claim 1, characterized in that the amount of copper is between 1 and 2% by weight. Alloy according to claim 1, characterized in that the amount of manganese is between 0.2 and 0.6% by weight. Alloy according to claim 1, characterized in that the amount of iron is greater than 50% by weight. Alloy according to claim 1, characterized in that it has a high-temperature disc pin slip wear resistance at 0.13 m / s by 255 m, less than 450 milligrams, measured using ASTM G99-90 at 260 ° C, with a 6.35 mm diameter and 25.4 mm long pin, Eatonite® 6 valve surface alloy pin, and a tested alloy disc having 50 Mm in diameter and 12.5 mm in thickness. Alloy according to claim 1, characterized in that it has a hardness at room temperature between 34 and 54 ° C on a Rockwell C scale. Alloy according to claim 1, characterized in that the amount of vanadium is between 0.02 and 3% by weight. Alloy according to claim 1, characterized in that the amount of niobium is between 0.02 and 3% by weight. Alloy according to claim 1, characterized in that it has a corrosion loss of less than 5 mg when 12.7 mm of a cylindrical alloy sample having a diameter of 6.35 mm and a length of 31.75 mm and heated to 149 ° 3, is immersed in a 0.25 vol% solution of sulfuric acid at room temperature, withdrawn, reheated, and the cycle repeated for 1 hour, with each cycle lasting 24 seconds.