Chromium-vanadium steels

Chromium-vanadium steel is an alloy steel combining high tensile strength and resistance to shock. ... 

It should be mentioned that, according to investigations of Bohme et al. [64], the adhesive forces (and hence the area of contact) remain altered if the material of the particle and substrate are interchanged for example, the adhesion of carbonyl iron powder to chromium—vanadium steel is the same as the adhesion of the steel powder to a carbonyl iron surface. 

Carbon steel is an alloy of iron with small amounts of Mn, S, P, and Si. Alloy steels are carbon steels with other additives such as nickel, chromium, vanadium, etc. Iron is a cheap, abundant, useful, and important metal. 

Carbon content is usually about 0.15% but may be higher in bolting steels and hot-work die steels. Molybdenum content is usually between 0.5 and 1.5% it increases creep—mpture strength and prevents temper embrittlement at the higher chromium contents. In the modified steels, siUcon is added to improve oxidation resistance, titanium and vanadium to stabilize the carbides to higher temperatures, and nickel to reduce notch sensitivity. Most of the chromium—molybdenum steels are used in the aimealed or in the normalized and tempered condition some of the modified grades have better properties in the quench and tempered condition. 

The above considerations will be illustrated by the simultaneous determination of manganese and chromium in steel and other ferro-alloys. The absorption spectra of 0.001 M permanganate and dichromate ions in 1M sulphuric acid, determined with a spectrophotometer and against 1M sulphuric acid in the reference cell, are shown in Fig. 17.20. For permanganate, the absorption maximum is at 545 nm, and a small correction must be applied for dichromate absorption. Similarly the peak dichromate absorption is at 440 nm, at which permanganate only absorbs weakly. Absorbances for these two ions, individually and in mixtures, obey Beer s Law provided the concentration of sulphuric acid is at least 0.5M. Iron(III), nickel, cobalt, and vanadium absorb at 425 nm and 545 nm, and should be absent or corrections must be made. 

Alloys other than those shown in Figure 1 are also suitable for resisting high temperature hydrogen attack. These include modifled carbon steels and low alloy steels to which carbide stabilizing elements (molybdenum, chromium, vanadium, titanium, or niobium) have been added. European alloys and heat-treating practices have been summarized by Class.11 Austenitic stainless steels are resistant to decarburization even at temperatures above 1000°F (538°C).12... 

Shiny silvery metal that is relatively soft in its pure form. Forms a highly resistant oxide coat. Used mainly in alloys, for example, in construction steel. Tiny amounts, in combination with other elements such as chromium, makes steel rustproof and improves its mechanical properties. Highly suited for tools and all types of machine parts. Also applied in airplane turbines. Chemically speaking, the element is of interest for catalysis (for example, removal of nitric oxides from waste gases). Vanadium forms countless beautiful, colored compounds (see Name). Essential for some organisms. Thus, natural oil, which was formed from marine life forms, contains substantial unwanted traces of vanadium that need to be removed. 

Colorimetric Methods are used only for the estimation of very small percentages of vanadium, e.g. in vanadium steels and alloys. The most important depend on the intensity of the reddish-brown colour produced by the action of hydrogen peroxide on an acid vanadate solution.3 If chromium is present, an equal amount must be introduced into the standard vanadium solution under the same conditions of temperature, acid concentration, etc. Phosphoric acid is added to destroy any yellow colour due to ferric iron, and either hydrofluoric acid or ammonium fluoride to destroy any colour produced by titanium.4 A colorimetric method for the simultaneous estimation of small quantities of titanium and vanadium has also been worked out.5 Other colorimetric processes are based on (a) the formation of a yellow to black coloration, due to aniline black, in the presence of aniline hydrochloride and potassium chlorate or other oxidising agent,6 and (b) the orange coloration finally produced when an acid solution of a vanadate is brought into contact with strychnine sulphate.7... 

The analysis of vanadium steels is effected by the application of one of the foregoing methods. Blank determinations on a steel free from vanadium but otherwise of the same approximate composition are used as a control. Iron and molybdenum are removed from hydrochloric acid solution by Kothe s ether separation method 1 chromium, nickel, copper, etc., are then precipitated as hydroxides by caustic soda, the filtrate containing the vanadium as vanadate.2 The method is modified for the simultaneous estimation of both vanadium and chromium in a vanadium-chromium steel.3... 

The first metal alloy developed specifically for use in bone plates was vanadium steel, invented in about 1905. Over the next two decades, a number of other alloys and metals were tried as bone plate materials. In 1926, another alloy designed especially for bone plates was invented. It was a type of stainless steel consisting of 18 percent chromium and 8 percent nickel. Later the same year, a slightly modified form of the alloy was introduced, called I8-8SM0, containing a small amount of molybdenum. 

Of the 106 or so natural and man-made elements, less than 20% are non-metals. At present, few of the metals are used to any large extent by man, either because of their rarity or their instability. The major "tonnage metals are iron, copper, aluminium, zinc, nickel, and lead. These metals may be alloyed with one another, such as copper and zinc to form brass, and/or may be alloyed with smaller quantities of other metals. Steels are commonly alloyed with chromium, vanadium, molybdenum, or tungsten. Aluminium, for increased lightness and strength, may be alloyed with magnesium. 

Transition metals have many uses in our society. Iron is used for steel copper for electrical wiring and water pipes titanium for paint silver for photographic paper manganese, chromium, vanadium, and cobalt as additives to steel platinum for industrial and automotive catalysts and so on. 

Steel is an iron aUoy containing smaU amounts of carbon (0.2 to 1.8 percent) and sometimes other elements such as chromium, manganese, nickel, tungsten, molybdenum, and vanadium. Steel cannot contain more than 1.8 percent carbon without becoming brittle, and the most common steels usually have closer to 0.2 percent carbon content. Commercial iron contains 2 to 4 percent carbon and is very brittle. Carbon steel contains only iron and carbon. 

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