Method for rapidly detecting nitrogen content in vanadium-nitrogen alloy

Abstract

The invention discloses a method for rapidly detecting the content of nitrogen in a vanadium-nitrogen alloy, and relates to the technical field of alloy detection. The method comprises the following steps: S1, preparing a sample; s2, sample pretreatment; s3, under the protection of inert gas, melting the sample by using pulse current, and detecting the released gas; the invention aims to solve the problems of tedious detection process and low efficiency of the nitrogen element in the vanadium-nitrogen alloy at present.

Description

Technical Field

[0001] The invention relates to the technical field of alloy detection, in particular to a method for quickly detecting nitrogen content in a vanadium-nitrogen alloy. Background Art

[0002] Vanadium-nitrogen alloy is a new type of alloy additive. It can be used in high-strength low-alloy steel. It can effectively carry out vanadium and nitrogen microalloying, promote the precipitation of carbon, vanadium and nitrogen compounds in steel, and more effectively play the role of sedimentation strengthening and grain refinement. It has more effective strengthening and grain refinement than ferrovanadium, and can replace ferrovanadium for microalloying production. Adding vanadium nitride to steel can improve the comprehensive mechanical properties of steel such as strength, toughness, ductility and thermal fatigue resistance, and make the steel have good weldability. When achieving the same strength, adding vanadium nitride can save 30%-40% of vanadium addition, thereby reducing smelting costs.

[0003] At present, the analysis method of vanadium nitrogen alloy mostly adopts chemical distillation method, which has a long analysis cycle and cumbersome operation, and cannot meet the fast-paced production requirements and quality control. How to simplify the analysis process, shorten the analysis time, reduce the analysis cost, reduce the consumption of reagents and energy, and make the analysis results fast, accurate and reliable has become an urgent need for the inspection of steelmaking auxiliary materials. Summary of the invention

[0004] The purpose of the present invention is to provide a method for rapid detection of nitrogen content in vanadium-nitrogen alloys, so as to solve the problem that the current detection process of nitrogen in vanadium-nitrogen alloys is complicated and inefficient.

[0005] In order to solve the above problems, the present invention adopts the following technical means: A method for quickly detecting nitrogen content in a vanadium-nitrogen alloy comprises the following steps: S1. Sample preparation; S2. Sample pretreatment; S3. Under the protection of inert gas, use pulse current to melt the sample and detect the released gas.

[0006] Preferably, in step S1, the sample is prepared by crushing and grinding, and the sample particle size is controlled to be no more than 180 meshes.

[0007] Furthermore, in step S2, the sample prepared in S1 is metal-coated to obtain a coated sample, and the coated sample is placed in a metal container.

[0008] Furthermore, the coated sample is metal coated with a nickel capsule, and the metal container is a nickel basket.

[0009] Furthermore, the nickel capsule is also coated with a solvent, and the solvent is tin particles.

[0010] Furthermore, the nickel capsule includes, by weight, 0.5 to 1 of the co-solvent and 0.05 to 0.15 of the sample prepared in step S1.

[0011] During use, the present invention has the following beneficial effects: Compared with the chemical analysis method, the analysis method of the present invention has a short cycle, accurate analysis results, good analysis precision, can help operators reduce labor intensity, greatly reduce analysis costs, has stronger operability, and is easy to promote and apply in production. Moreover, compared with the chemical analysis method, the analysis and detection time of the N element in the vanadium nitrogen alloy sample is shortened from 6 hours per sample to 5 minutes per sample. The original method detects 1 sample in 6 hours, and this method detects 72 samples in 6 hours. In addition, no consumables such as chemical reagent materials are required, which can greatly reduce the production and detection costs. DETAILED DESCRIPTION

[0012] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments.

[0013] Therefore, the following detailed description of the embodiments of the present invention is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0014] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features of the embodiments may be combined with each other.

[0015] A method for quickly detecting nitrogen content in a vanadium-nitrogen alloy comprises the following steps: S1. Sample preparation; S2. Sample pretreatment; S3. Under the protection of inert gas, use pulse current to melt the sample and detect the released gas.

[0016] In this way, a low current is loaded between the upper and lower electrodes of the pulse electrode furnace to heat the sample in the graphite crucible. The nitrogen in the sample is detected by the thermal conductivity method (TCD), and the detected gas is converted into a signal corresponding to this concentration. The signal is rectified, filtered, amplified, and integrated to obtain the final measurement result.

[0017] Specifically, when current passes through the graphite crucible sandwiched between the upper and lower electrodes, the temperature of the crucible rises rapidly due to the Joule heat generated, and the sample therein undergoes thermal decomposition, with oxygen released in the form of CO and nitrogen released in the form of N2, whose concentrations are then detected by an infrared detector and a thermal conductivity cell, respectively.

[0018] Specifically, for the establishment of the working curve, a vanadium-nitrogen alloy standard sample with an appropriate N element content gradient is selected to test and draw a standard curve, and the determination conditions of the EMGA-820 oxygen-nitrogen analyzer for rapid determination of the N element content in the powder sample-vanadium-nitrogen alloy are set, and the analysis program is edited, the basic information of the sample is compiled, the value of the N element in the standard sample is input, the absorption integral of the standard sample is measured, and a regression calculation is performed based on the relationship between the integral intensity of N and the mass fraction to obtain the N element calibration curve coefficients and store them in the analysis program for measuring the sample.

[0019] Preferably, in step S1, the sample is prepared by crushing and grinding, and the sample particle size is controlled to be no more than 180 meshes.

[0020] Furthermore, in step S2, the sample prepared in S1 is metal-coated to obtain a coated sample, and the coated sample is placed in a metal container.

[0021] Meanwhile, the coated sample is metal coated with a nickel capsule, and the metal container is a nickel basket.

[0022] Moreover, the nickel capsule is also coated with a flux, which is tin particles.

[0023] Furthermore, the nickel capsule includes 0.5 to 1 parts of the co-solvent and 0.05 to 0.15 parts of the sample prepared in step S1, by weight.

[0024] Specifically, since the vanadium nitrogen alloy is a powder sample, the vanadium nitrogen alloy sample must be pretreated before analysis. First, the powder sample must have metal The container is used to hold and wrap the sample to form metal particles; a nickel basket or a nickel bag is used to hold or wrap the sample. The weighed sample is placed into the nickel bag, and the mouth of the nickel bag is sealed with sealing pliers to form metal particles for later use.

[0025] Moreover, since the nitrogen content in the vanadium nitrogen alloy is as high as about 20%, if too much sample is weighed, gas will escape due to the high content in the analysis and detection. Therefore, according to the needs of this application, the different weighing amounts of the vanadium nitrogen alloy are determined to be 0.05g, 0.10g and 0.15g; and the flux (high-purity tin particles) are selected in three different addition amounts: 0.00g, 0.50g and 1.00g. In addition, a vanadium nitrogen alloy standard sample YSBC28649-2015, in which the N content is 14.08%, is selected to test the weighing amount and the amount of flux added. The specific results are shown in Table 1: Through the test with standard samples, it was verified that only when the sample weight was 0.10g and 0.5g of high-purity tin flux was added, the analysis result was closest to the standard value.

[0026] In summary, in this embodiment, when the EMGA-820 oxygen and nitrogen analyzer is used to quickly determine the N element content in the vanadium-nitrogen alloy sample, the pretreatment of the sample is very critical. When the sample is wrapped in a nickel bag, it is important to pay attention to the tight sealing of the nickel bag, and to avoid excessive force when folding the nickel bag, which may cause the nickel bag to break and leak the sample. During the analysis of the melting process, the sample will adhere to the feed port, affecting the analysis results and causing damage to the instrument. In addition, it is also important to avoid sharp edges when folding the package to avoid material jamming at the feed port and causing instrument failure.

[0027] The sample was packed in a nickel capsule to make metal particles, and the EMGA-820 oxygen and nitrogen analyzer was used. Rapid determination of N element in powder sample - vanadium nitrogen alloy sample. Compared with chemical analysis method, the analysis cycle is short (chemical method tests 1 sample in 6 hours; oxygen and nitrogen analyzer tests 12 samples in 1 hour), the analysis result is accurate, the analysis precision is good, it can help operators reduce labor intensity, greatly reduce analysis costs, effectively expand the online analysis field of EMGA-820 oxygen and nitrogen analyzer, with stronger operability and easy to promote and apply in production.

[0028] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for rapid detection of nitrogen content in vanadium-nitrogen alloy, characterized in that: The following steps are involved: S1. Sample preparation; S2. Sample pretreatment; S3. Under the protection of inert gas, use pulse current to melt the sample and detect the released gas.

2. The method for rapid detection of nitrogen content in vanadium-nitrogen alloy according to claim 1, characterized in that: In step S1, the sample is prepared by crushing and grinding, and the sample particle size is controlled to be no more than 180 meshes.

3. The method for rapid detection of nitrogen content in vanadium-nitrogen alloy according to claim 1, characterized in that: In step S2, the sample prepared in S1 is metal-coated to obtain a coated sample, and the coated sample is placed in a metal container.

4. The method for rapid detection of nitrogen content in vanadium-nitrogen alloy according to claim 3, characterized in that: The coated sample is metal coated with a nickel capsule, and the metal container is a nickel basket.

5. The method for rapid detection of nitrogen content in vanadium-nitrogen alloy according to claim 4, characterized in that: The nickel capsule is also coated with a solvent, which is tin particles.

6. The method for rapid detection of nitrogen content in vanadium-nitrogen alloy according to claim 5, characterized in that: The nickel capsule includes 0.5 to 1 parts of the co-solvent and 0.05 to 0.15 parts of the sample prepared in step S1, by weight.

Images