METALLURGY. 

 4bb 



wait, that these alloys behave exactly as sible to use this alloy instead of platinum in the 



M- Dilutions do, and he has thus ailorded a 



in the 



pn 



steel. , 



In a new method of producing 

 armor plate of uniform composition the nventor 

 M. Werth, manager of a large iron and steel works 

 in France, takes advantage of the fact that by 

 suitably controlling the process of cooling it is 

 possible to obtain some of the newer alloys ol 

 ron and steel with nickel, cobalt, and manganese 

 in either a hard or a malleable condition. The in- 

 ventor contends for a plate having the same chem- 

 ical composition throughout, the hardening ol the 

 fa<i> being effected by tempering. In the working 

 of his process he finds that when the steel is 

 alloyed with suitable proportions of the other 

 metal it is possible to obtain the alloy m a hard 

 state by heating it uj. to a bright red and allowing 

 it to cool in the aii 



obscure One of the more recent applications of the 

 X-rays has been to the study of metallic alloys. 

 When an alloy is composed of two metals hav- 

 ing different transparencies to the rays radio- 

 graphs taken of thin plates show the separation 

 of the two during solidification. Thus it has 

 been observed that an alloy of aluminum and 

 gold shows on solidification the segregation of 

 a definite compound of the two metals, which 

 separates in well-defined crystals. 



In an investigation conducted by the German 

 Admiralty for determining the action of sea water 

 of the on alloys 9 out of 12 strips each of copper, zinc, 

 tin, aluminum, and iron-aluminum alloys were 

 immersed in sea water, and the remaining 3 of 

 eaph set were reserved as standards. The experi- 

 ments were each continued for two years, while 

 3 strips were withdrawn from the water at the 



hard-faced 



1M , . whereas" if it is heated only end of eight months for testing^of^their^ physical 

 I,, a dull red and cooled, it will be malleable and 

 comparatively soft. 



In a paper l>efore the American Institute ol 

 Mining Engineers Mr. E. S. Sperry has pointed 

 that the occurrence of cracks during the 



-- .. - 



properties and comparison with the standards. 

 The iron, tin, and aluminum bronzes deteriorated 

 but little, and showed no marked differences in 

 appearance, weight, or strength, even after from 

 two to two and a half years', immersion. When 



a serious 



out that the occurrence 01 cracKs uuimg me ^"v ^ ,.~ - ., -- 



rollini; of brass is often due to the presence of iron and tin bronzes were m contact 



purities in the copper of the alloy^ In some alteration of the iron material was noticed. Cast 



of his investigations the author added to a brass and wrought bronze behaved m a similar way 



ition. made of 60 per cent, of pure copper The conclusion was deduced from the tests that 



f .^IA.- ~t :,^-rT fV>o nr>vvr>ei\7P affirm hpT.wpen the dmerent metals 



unp 



and '40 per cent, of zinc, "quantities of antimony the corrosive action between the different metals 



against the action of sea water "when in contact 



varvin.' 'from 0.01 per cent, to 0.65 per cent., and depends on their position in the electrical scale 

 tested in the rolling mill the behavior of the Thus pure aluminum bronze ^ practically^proof 

 nllnv^ thus obtained. When the percentage of 



thus obtained. When the percentage 

 antimony reached as much as 0.02 per cent., the 



with metals that are electro-negative toward it. 



fracture* of the rolled metal indicated its pres- In experiments on the deterioration of certain 



ence. The author therefore believes that the pres- alloys under the action of the atmosphere, it was 



ence of antimony in electrolytic copper is the shown that iron bronze suffered practically no 



cause of the unreliability of brass in rolling. injury, but alloys containing a large proportion 



An alloy of aluminum and magnesium consid- of zinc were easily corroded. 



erably lighter than aluminum has been obtained Observations for the determination of mag- 



bv Mach. With 10 per cent, of magnesium the netic properties have been made by Dr. S. W. 



alloy resembles zinc; with 15 per cent., a variety Richardson upon four alloys of iron and alumi- 



of brass; and with 25 per cent., a kind of bronze, num, containing respectively 3.64, 5.44, 9.89, and 



All these alloys can be soldered. The alloy of 18.47 per cent, of aluminum. The alloys were 



from 10 to 12 per cent, of magnesium, which used in the form of anchor rings, and were wound 



with primary and secondary coils separated by 

 asbestos paper. The temperature applied ranged 



has been more fully studied, is nearly as white 

 as silver, and hard enough for a sharpened piece 

 to cut aluminum. It can be turned, bored, and 



from 83 C. to 900 C. The chief conclusions 



tapped, and seems to be well adapted to the to be drawn from the experiments may be summed 

 making of instruments of precision, as in the up as follow: 1. .The alloys behave magnetically, 



mounting of lenses, graduated circles, etc. 



A new form of metal, denominated " copper- 

 steel," has been brought out in Paris. It is de- 



Bcribed as possessing a very high resistance, and critical point seem to indicate that the alloys 

 can be forged like iron. It is manufactured by are heterogeneous in structure. 3. The perme- 



as though they consisted of two distinct media 

 superposed. 2. The general roundness of the 

 curves and their lack of abruptness near the 



a process during which zinc or its alloys is em- 

 ployed for retaining a certain proportion of iron, 



ability decreases with rise of temperature near 

 the critical point until a minimum value is 



nickel, or chromium in the form of oxide, and reached, when further rise of temperature pro- 

 redneing and incorporating it in a state of fine duces very slight diminution, if any, in the per- 

 division in the presence of furnace gases. A num- meability. 4. The experiments suggest that the 

 ber of new alloys, it is stated, are thus obtained, maximum value of the permeability for an alloy 

 and among them the metal referred to under the containing 10 per cent, of aluminum is reached 



at about 90 C. 5. An alloy containing 18.4? 

 per cent, of aluminum has a critical point at 

 about 25 C., and gives no indication of tempera- 

 ture hysteresis. A second maximum on the in- 

 duction curve was found at high temperatures, 



title designated. 



The leading-in wires for attaching the carbon 

 filament and making electric connections in elec- 

 tric incandescent lamps have so far been made 

 of platinum, because that was the onlv metal 



known which had the same rate of expansion and which becomes less and less noticeable as the field 



contraction as glass, and the only one which could is increased. 



be used without a liability to generate a leakage New Processes. The Cowper-Coles electro- 



>f air into the bulb. It has recently been found galvanizing process, which has been used for coat- 



Hiat the coefficient of expansion of iron-nickel ing boilers of the water-tube class and a large 



Hoys varies according to the percentages of the number of torpedo-boat destroyers, has been 



wo metals present, and that one containing 45 greatly improved recently, on account of which 



per cent, of nickel has the same rate of expan- a number of plants employing it have been re- 

 ion as platinum. It may therefore be pos- modeled. The system consists in using zinc dust 



