US1977270A - Ornamental rustless iron product and art of making the same - Google Patents

Description

Patented Oct.-

1,977,270 ORNAMENTAL RUSTLESS IRON PRODUCT 1 a ART oF MAKING THE SAME AlexandenIaFeild, Baltimore, Md., assignor to Alloy Research Corporation, Baltimore, Md.

no Drawing.

11 Claims.

This invention relates to an ornamental rustless iron or steel product and to an art of producing the same.

Among the, objects of my invention are the 5 production in a simple, efiicient and thoroughly practical manner of a rustless iron product'or manufacture which is decorative, ornamental and attractive to the eye; a product that is strong, tough, durable as well as corrosion-resistant or rustless; one that is adapted to exterior ornamental or decorative work such as balconies, rails, fences and gates, and especially to interior applications such as rails, trim, grilles or inside balconies as well as objects of art such as urns, bowls or vases, or ornamental hardware such as locks, hinges, hasps, and the like; and which retains its decorative or ornamental characteristics under the many varying conditions of actual practical use.

The invention, accordingly, consists in the features of construction, combination of elements and arrangement of parts, and in the several steps and the relation of each of the same to one or more of the others as described herein and 25 the scope of the application of which is indicated in the following claims.

As conducive to a clearer understanding of certain features of my invention it may at this point be noted that in heretofore known and/or used methods of producing corrosion-resistant decorativeornamental ironwork, for either interior or exterior applications, either a rough, scaly surface is allowed to remain on the rustless iron product, when the appearance is of no consequence, or the scale is removed by sand-blasting,

grinding and/or pickling to give a dull smoothfinish, or the surface of the product may then be buffed or polished whereby a finish ranging from a satin to a bright mirror-like surface is achieved as desired.

Also, in -heretofore known and/or used methods of producing ornamental ironwork, the product may be given a final finish of a desiredcolor and surface quality by a suitable paint, cement or other coating compound. Such coatings, in addition to being initially expensive, are of necessity impermanent, requiring constant attention and repair with frequent renewal at considerable inconvenience and expense.

One of the objects of my invention is the production of a rustless iron decorative or ornamental product in a simple, enexpensive, eflicient and thoroughly reliable manner, having a surface, 55 permanent and corrosion-resistant, which is Application November 2, 1932, Serial No. 640,902

pleasing and attractive to the eye both as to color and as to quality and finish.

Referring now more particularly 'to the manner of producing a decorative or ornamental product, illustratively a piece of ornamental hardware, in accordance with my invention, a piece of sheet, strip, plate or bar stock of a rustless iron (a ferrous alloy containing from 12-25% chromium and about .15% carbon, either with or without additional alloying elements such as nickel, 35 copper, tungsten and vanadium); is first cut, stamped and otherwise shaped to conform to a desired pattern or design. The shaping may be carried out either with the stock hot or cold, depending upon the shape ofobject desired and the 7 amount of working necessary.

Thus, for example, a piece of rustless iron plate stock analyzing 17% chromium, .08% carbon, with small amounts of silicon and manganese and traces of sulfur and phosphorus, is forged to form a fancy ornamental hinge.

To relieve internal stresses incident to the forging, the product is conveniently annealed by heating it for about two hours at a temperature of approximately 1525 F. and then allowing it to slowly air cool at normal room temperature.

As a result of the working and annealing indicated above a scale is formed on the product. This scale is conveniently removed by pickling the product in a bath comprising an aqueous solution of 20% nitric acid and a 1% solution of hydrofluoric acid. After the scale is fully removed, traces of the picking solution are removed by washing the product in running water. Conveniently the product is dried in any suitable manner before a further working of its surface is undertaken.

To give a wrought or reticulate appearance which is ornamental and pleasing to the eye', the article is hammered in any convenient fashion, as with the ball-peen of a machinist hammer, until the surface is suitably covered with a myriad of small indentations which may cover the entire surface exposed to view or any part of it as desired.

The article or product is then preferably dipped in a 10% nitric acid solution to free its surface of any minute adhering particles of iron from the hammer or other tool with which its surface has just been worked. This dip may be followed by washing and drying the product in any convenient fashion.

An attractive finish is given the article by heating it until the surface becomes tinted to, for example, the rich color of old gold. Rustless iron, as in the case of ordinary low carbon iron, progressively passes through the various colors light straw, dark straw, yellowish-brown, redbrown, deep purple, violet, blue and green as the product is gradually heated. In the case of rustless iron, however, the band of colors ranging from light straw to yellowish brown is broadened out, these colors persisting longer during the heating of the product. By a reasonably careful control of the length of time that the product is exposed to the source of heat as compared with the temperature of the heating agent, a deep rich color of old gold may be given the surface ing the article during the heating period and the the many desirable characteristics of rustless,

length of time that the article is subjected to the heating action of the heating agent.

Thus, for a fiat, relatively thin article, such as an ornamental hinge, a desired old gold finish is achieved by subjecting the hinge to the heat of a gas-fired furnace operating at a temperature of about 1750 F. for a period of some fifty seconds.

Another ornamental and attractive finish may be given the article by further treatment of grinding or polishing off the outermost portions of the reticulations as by means of an emery belt or other abrading machine to expose the silver white metal beneath. The contrast between the spots of dull gold color and those of the bright silvery appearance produces a pleasing and highly artistic efiect.

Before using the article, finished either with or without the further treatment described above,

, it is preferably given a passivating treatment by dipping in an aqueous solution of 10% nitric acid.

. The surface of the article is then washed clean under running water and suitably dried.

A' product or article having the many beneficial characteristics of rustless iron, such as its corrosion-resistant, hardness and strength, coupled with the durable and attractive heat-tinted finish is thus produced without in any way affecting the rustless or corrosion-resistant characteristics of the material.

For example,.an article prepared in accordance with my process withstands a standard loo-hour salt-spray test (4% sea-salt solution) without showing any appreciable corrosion or discoloration.

Thus it will be seen that there has been-provided in this invention an art and product in which the various objects hereinbefore noted,

together with many thoroughly practical advantages are successfully achieved. It will be seen that the product is strong, durable and corrosionresistant, and that it is given a permanent and attractive finish in a simple, direct and thoroughly practical manner all without sacrifice to iron.

While in treating the shaped article, as hereinbefore described, a wrought or reticulated'surface was given it prior to the heat tinting thereof, certain beneficial results, such as a smoother but somewhat duller finish to the depressed areas, may be achieved by heat-tinting the article first and then giving its surface the wrought appearance. Or, if desirable, the article may be used with the smooth old gold colored satin finish without the wrought or reticulated eifect.

Similarly, certain economies in practice, such as saving in time and expenditure of effort, may be achieved by working the article at the heattinting temperature.

As many possible embodiments may. be made of my invention and as many changes or alterations may be made in the embodiment hereinbefore set forth, itis to be understood that all matter described herein isyto be interpreted as illustrative and not in a limiting sense.

1. Ina manufacture of the class described, a rustless iron product having a corrosion-resistant heat-tinted surface.

2. In a manufacture of'the class described, a rustless iron product having an indented or reticulated corrosion-resistant heat-tinted surface.

3. In a manufacture of the class described, a rustless iron product having an indented or reticulated corrosion-resistant heat-tinted surface, the outermost portions of which are removed to expose the base metal.

4. In a manufacture of the class described, a rustless iron product having a corrosion-resistant surface heat-tinted to about the color of old gold.

5. In a manufacture of the class described, a rustless iron product having a reticulated corrosion-resistant surface heat-tinted to about a straw color.

6. In a manufacture of the class described, a rustless iron product having a reticulated corrosion-resistant surface, the reticulated portions of which are heat-tinted to a straw color and the remaining portions of which are of the bright base metal.

'7. In a manufacture of the class described, the art which comprises, heat-tinting a rustless iron product to a straw color to give a corrosion-resistant tinted surface.

8. In a manufacture of the class described, the art which comprises, producing a wrought product of rustless iron, and then heat-tinting the surface of said product to an old gold color without detracting from the rustless or corrosionresistant character of the product.

9. In a manufacture of the class described, the art which comprises, heat-tinting a rustless iron product to give a corrosion-resistant tinted surproducing a wrought effect without detracting .from the rustless character of the surface.

10. In a manufacture of the class described, the art which comprises, deforming a rustless iron product to give a surface having a wrought appearance, heating the product to produce a tinted surface, and then removing a portion of the heattinted surface to expose the underlying rustless metal of the product.

11. In a manufacture of the class described, the art which comprises, deforming a rustless iron product at a temperature sufiiciently high so as to cause a heat-tinting of the surface of the product during the deformation thereof whereby a desired corrosion-resistant tinted surface of a1 wrought metal product is achieved.

ALEXANDER L. FEILD.