High-chromium, or what is called stainless steel containing from 11 to 14 per cent chromium, was originally developed for cutlery purposes, but has in the past few years been used...
The information given on the various parts of the Liberty engine applies with equal force to the corresponding parts in the construction of an automobile, truck or tractor. We reco...
Impact tests are of considerable importance as an indication of how a metal will perform under shock. Some engineers think that the tensile test, which is one made under slow loadi...
Pyrometers for molten metal are connected to portable thermocouples as in Fig. 132. Usually the pyrometer is portable, as shown in this case, which is a Brown. Other methods of mou...
As a general rule steel should be worked when it is in the austenitic state. (See page 108.) It is then soft and ductile. As the steel is heated above the critical temperature the...
Carbon tool steel, or tool steel as it is commonly called, usually contains from 80 to 125 points (or from 0.80 to 1.25 per cent) of carbon, and none of the alloys which go to make...
Uneven heating and poor quenching has caused loss of many very valuable dies, and it certainly seems that when a firm spends from $75 to $450 in cutting a die that a few hours coul...
In the new method, the packed pots are run into the case-hardening furnaces, which are heated to 1,600 deg.F. On the insertion of the cold pots, the temperature naturally falls. Th...
Although the advantages offered by the gas-fired furnace for carburizing have been generally recognized in the past from points of view as close temperature regulation, decreased a...
Such portable flame shields as the one illustrated in Fig. 106 may prove serviceable before furnaces required for plate work, where the doors are often only opened for a moment at...
For the complete calibration of a thermo-couple of unknown electromotive force, the new couple may be checked against a standard instrument, placing the two bare couples side by si...
Parts of this general type should be heat-treated to show the following minimum physical properties: Elastic limit, 115,000 lb. per square inch; elongation in 2 in., 16 per cent; r...
Proper annealing of low-carbon steels causes a complete solution or combination to take place between the ferrite and pearlite, producing a homogeneous mass of small grains of each...
The effect of heat treatment on overheated steel is shown graphically in Fig. 65 to the series of illustrations on pages 137 to 144. This was prepared by Thos. Firth & Sons, Ltd.,...
All high-carbon tool steels are heated in a cyanide bath. With this bath, the heat can be controlled within 3 deg. The steel is evenly heated without exposure to the air, resulting...
For years the toolmaker had full sway in regard to make of steel wanted for shop tools, he generally made his own designs, hardened, tempered, ground and usually set up the machine...
An easy and convenient method for standardization and one which does not necessitate the use of an expensive laboratory equipment is that based upon determining the melting point o...
Of all the opportunities for practicing economy in the heat-treatment department, there is none that offers greater possibilities for profitable returns than the systematic cleanin...
Essentially, this consists of the sturdy, power-driven separator and fanning mill which separates the foreign matter from the compound and elevates it into a large settling basin w...
The size of the piece influences the physical properties obtained in steel by heat treatment. This has been worked out by E. J. Janitzky, metallurgical engineer of the Illinois Ste...
The quenching tank is an important feature of apparatus in case-hardening--possibly more so than in ordinary tempering. One reason for this is because of the large quantities of pi...
The quality of high-speed steel is dependent to a very great extent upon its structure. The making of the structure begins under the hammer, and the beneficial effects produced in...
The following table shows the percentages of carbon, manganese, nickel, chromium and vanadium in typical steel alloys for engineering purposes. It also gives the elastic limit, ten...
The highly stressed parts on the Liberty engine consisted of the connecting-rod bolt, the main-bearing bolt, the propeller-hub key, etc. The material used for parts of this type wa...
According to Guillet, the absorption of carbon is favored by those special elements which exist as double carbides in steel. For example, manganese exists as manganese carbide in c...
By the use of compensating leads, formed of the same material as the thermo-couple, the cold junction can be removed from the head of the thermo-couple to a point 10, 20 or 50 ft....
Heat treatment consists in heating and cooling metal at definite rates in order to change its physical condition. Many objects may be attained by correct heat treatment, but nothin...
We will now take up the matter of hardening high-speed steels. The most ordinary tools used are for lathes and planers. The forging should be done at carbon-steel heat. Rough-grind...
Strength of a metal is usually expressed in the number of pounds a 1-in. bar will support just before breaking, a term called the ultimate strength. It has been found that the shap...
FIRE.--For these tools a good fire is one made of hard foundry coke, broken in small pieces, in an ordinary blacksmith forge with a few bricks laid over the top to form a hollow fi...