The invention discloses an observation method of a niobium-tungsten-molybdenum alloy metallographic structure. The method comprises the following steps: 1, machining an observation surface of a niobium-tungsten-molybdenum alloy sample into a plane, then grinding on a metallographic grinder; rinsing sand grains on the sample after grinding; 2, putting the niobium-tungsten-molybdenum alloy sample with the sand grains being removed on a polishing machine for mechanical polish; 3, soaking the mechanically polished niobium-tungsten-molybdenum alloy sample into polishing solution for chemically polish, and then rinsing the sample by clean water; 4, soaking the chemically polished niobium-tungsten-molybdenum alloy sample into etchant solution for erosion, so that the surface of the niobium-tungsten-molybdenum alloy sample is silver gray; 5, putting the niobium-tungsten-molybdenum alloy sample eroded by the etchant solution under a microscope to carry out metallographic structure observation. The method disclosed by the invention is easy to operate without any special device, and the niobium-tungsten-molybdenum alloy metallographic structure can be clearly observed.

Observation method of niobium-tungsten-molybdenum alloy metallographic structure

The invention discloses a method for observing a metallographic structure on a Monel alloy/steel surfacing interface. The method comprises the following steps of: 1, machining a metallographic observation plane on the Monel-400 alloy/steel surfacing interface, grinding, and washing off sand particles; 2, mechanically polishing; 3, eroding a Monel-400 alloy part in the mechanically polished metallographic observation plane by adopting an erosion solution, and cleaning a steel part in the metallographic observation plane by adopting a nitric acid alcohol solution; and 4, observing the metallographic structure under a microscope. By the method, the Monel-400 alloy part of the Monel-400 alloy/steel surfacing interface is eroded with the erosion solution which is a mixture of an HCl saturated solution, an H2SO4 saturated solution, an HNO3 saturated solution and a CuSO4 saturated solution, so that severe erosion influence of an erodent on steel is avoided, and the structural hierarchy of a Monel-400 alloy surfacing layer is clear. The method is easy to operate; no special equipment is required; and the metallographic structure on the Monel-400 alloy/steel surfacing interface can be clearly observed.

Method for observing metallographic structure on Monel alloy/steel surfacing interface

The invention discloses a corrosion method of high niobium titanium alloy. A to-be-etched surface of a polished metallographic sample is wiped with a corrosion solution for 3 to 5 times, then with anoxidizing solution for 3-5 times, and alternately-repeated wiping is performed until a better result is achieved. Different tissues are different in degrees of difficulty to generate oxide films, andsubsequent corrosion is further affected, so that the display contrasts of the different tissues are different. The corrosion method can realize the metallurgical corrosion of the high niobium titanium alloy in a rolled state, a solid-solution state and an aged state. The grain boundary and the phase boundary of the obtained sample are clear and complete, and the operation is simple, convenient and fast. The method solves the problems of low contrast and difficulty of distinguishing of the tissues in a metallographic picture in the high niobium titanium alloy after corrosion, and the problem that the aged high niobium titanium alloy is difficult to corrode.

Corrosion method of high niobium titanium alloy

Method for evaluating quality of centrifugal casting alloy furnace tube

The invention provides a metallurgical corrosive and a metallurgical structure display method, wherein the metallurgical structure display method comprises the following steps: providing a niobium or niobium alloy metallurgical test sample; mechanically grinding the niobium or niobium alloy metallurgical test sample; mechanically polishing the niobium or niobium alloy metallurgical test sample after mechanical grinding; and immersing the niobium or niobium alloy metallurgical test after mechanical polishing into the metallurgical corrosive, wherein the metallurgical corrosive is a mixed solution of hydrofluoric acid, nitric acid and sulfuric acid. By adopting the metallurgical structure display method provided by the invention, the step of electrochemically polishing niobium or niobium alloy in the prior art can be omitted, the efficiency of corroding the niobium or niobium alloy and the metallurgical structure display efficiency are greatly improved, and a good crystal orientation display effect can be further obtained.

Metallurgical corrosive and metallurgical structure display method

The invention relates to a method for observing the metallographic structure of niobium-titanium alloy, which is characterized by comprising the following steps of: firstly, grinding a sample on a grinding machine, polishing the sample on a polishing machine, and chemically polishing the sample in a mixed solution of sulfuric acid + nitric acid + hydrofluoric acid; then, selecting a reagent of sulfuric acid + nitric acid + hydrochloric acid + hydrofluoric acid to erode the sample, and observing the metallographic structure By using the method, the metallographic structure of niobium-titanium alloy can be observed clearly The method provided by the invention is easy to operate without any special equipment, and good effect is achieved in the preparation of a metallographic sample of niobium-titanium alloy

Method for observing metallographic structure of niobium-titanium alloy

The invention discloses a sample treatment method for observing a nuclear-grade silver-indium-cadmium control bar macrostructure. The method comprises the following steps: one, machining a nuclear-grade silver-indium-cadmium control bar to obtain an observation plane; two, successively grinding and polishing the nuclear-grade silver-indium-cadmium control bar observation plane; three, carrying outone-time scratching on the polished nuclear-grade silver-indium-cadmium control bar observation plane; four, carrying out secondary scratching on the nuclear-grade silver-indium-cadmium control bar observation plane after one-time scratching is carried out, and then observing the nuclear-grade silver-indium-cadmium control bar after second-time scratching is carried out. A first corrosive agent which consists of an H2O2 solution, an ammonia water solution and water is used at first to remove dust, greasy dirt and a compact oxidation layer on the nuclear-grade silver-indium-cadmium control barobservation plane, thus, an alloy surface is exposed, then internal tissues of the nuclear-grade silver-indium-cadmium control bar appear by a second corrosive agent which consists of acetic acid, ethanol and nitric acid, then observation is carried out, and the method is simple, convenient and speedy.

Sample treatment method for observing nuclear-grade silver-indium-cadmium control bar macrostructure

The invention discloses a method for observing an iron-nickel-chromium alloy metallographic structure. The method comprises the following steps: 1, machining an observation plane on iron-nickel-chromium alloy and grinding; 2, polishing the observation plane of the iron-nickel-chromium alloy; 3, performing corrosion wiping on the polished observation plane of the iron-nickel-chromium alloy by a corrosive agent; 4, performing electrolytic corrosion on the observation plane, subjected to corrosion wiping, of the iron-nickel-chromium alloy; and 5, performing metallographic structure observation onthe observation plane, subjected to electrolytic corrosion, of the iron-nickel-chromium alloy by a microscope. According to the method, pollutants such as dust and oil dirt as well as an oxidation layer on the observation plane of the iron-nickel-chromium alloy are removed by an acidic corrosive agent and then the observation plane of the iron-nickel-chromium alloy is subjected to oxidation reaction through electrolytic corrosion to lose electrons to be corroded, so that a clear microscopic structure is obtained, the method is convenient and flexible, formation of an oxidation film is avoidedand generation of pseudo structures is avoided.

Wu Jingjing

Papers

Method for observing metallographic structure of niobium-titanium alloy

Sample treatment method for observing nuclear-grade silver-indium-cadmium control bar macrostructure

Method for observing iron-nickel-chromium alloy metallographic structure