The three distinct groups of the alloyed cast irons, which have enhanced heat and corrosion resistance for specific environment, are 1. Cast materials at a glance description material material chemical composition reference values, wt. One type of cast iron is en gjnhv520 nihard 2 containing 2. Highchromium 2234 per cent cast iron alloys and their. Nickelchromium white irons the oldest group of highalloy irons of industrial importance, the nickelchromium white irons, or ni hard irons, have been produced for more than 50 years and are very costeffective materials for crushing and grinding. Colour metallography of cast iron by zhou jiyang, professor, dalian university of technology, china. So in the pearlitic grade of the ductile iron the copper is kept between 0. Astm a532 class i type a nihard 1 high chrome white iron. These are four digit numbers which represent chemical composition standards for steel specifications.
On chinese new years eve, all family members return to the family house to have a feast called ni ny8f0n. Mastering photographic composition, creativity, and personal style alain briot. Ni hard 4 is a class of cast iron alloys, which contains 3 wt% c, 810 wt% cr, 46 wt% ni and 1. Microstructural analyses are performed randomly and each casting is checked for proper hardness at several intervals during production. Pdf optimization of graphite morphology in mottled nihard cast. Steel and iron handbook niir project consultancy services. Pdf control of carbides and graphite in nihard type. Chromium is the hardest of the most commonly deposited metals. Since this can be a large number, the prefix mega is used to indicate 1,000,000 units and the term meganewton per square meter mnm 2 is used. Ni hard 1 and 2 are highly resistant to abrasion and impact and also provides toughness because of the less carbide. Properties and applications of niresist and ductile ni. The class i type d ni hard 4 alloy is a modified nickelchromium iron that contains higher levels of chromium, ranging from 7 to 11%, and increased levels of nickel, ranging from 5 to 7%. Nihard has a microstructure consisting of carbides and a martensitic austeniticbainitic or predominantly martensitic matrix. Ni hard irons high crmo irons high chromium irons physical properties of cast irons.
The books homepage helps you explore earths biggest bookstore without ever leaving the comfort of your couch. Balance average hardness 300 hbn 800 hbn white iron maxalloy 5 maxalloy 2 maxalloy 5a nihard 4. Why does stryver continually criticize and belittle sydney carton for his social lapses from tales of two cities book 2 chapter 11. Chemical composition ranges of the outer ring layers expressed in weight percent wt %. This book is intended as a resource and as an introduction to the layman about our most important metal system. Effect of basic chemical element in sgi ductile iron. The chemical compositions of the alloys were determined by wet. Heat treatments of castings, shop floor melt quality tests. Specific targets will vary, depending on bar size, although the ranges listed are required. Investigating the effect of titanium addition on the microstructure and mechanical properties of ni hard 4 cast iron masoud bahrami alamdarlo 1, kamran amini 2, vahid nemati najafabadi 1. Solidification begins in the mold, and continues through the first zone 4 and strand guide 5. Ni resist type 2 will be similar to type 1 having an austenitic matrix with approximately 510% alloy carbide. Nihard 1 and 2 are essentially 4% ni, 2 % cr irons. I, type b, such as ni hard 4 but excels in corrosion resistance over this class of irons.
The term for force per unit of area stress is the newton per square meter nm 2. Hc28 owes its abrasion resistant properties to the various chromium iron carbides in the microstructure. Referring to figure 2, liquid steel flows out of the ladle 1 into the tundish 2, and then into a watercooled copper mold 3. Chemical composition of durabar 202 ni resist the chemical composition for durabar 202 ni resist is shown in table 1 below. Stourvale road, lye, stourbridge, west midlands dy9 8pr telephone. Ni hard 4 is designed to give a microstructure of eutectic m 7 c 3 carbides embedded in a metallic matrix that is predominantly austenitic in the ascast condition. Chemical compositions of the alloys are listed in table 1. Control of carbides and graphite in ni hard type cast iron for hot strip mills article pdf available in materials science forum 561565 january 2007. Our concern for the rest of this paper, however, will be with hard chrome plating. Table 53 lists the chemical composition of ni hard. Nickel alloy steels substitute nickel in place of roughly half of standard. Pdf effects of molybdenum addition on the microstructure and. Highchromium 2234 per cent cast iron alloys and their simulated behaviour at the sugar industry e zumelzu, 0 opitz and c cabezas.
Investigating the effect of titanium addition on the. Nihard white irons, bainite, martensite, austenite, abrasion resistant iron. Wear resistance of nihard 4 and highchromium cast iron. Nihard 1 should also be considered if there are low or medium dynamic stresses. Comparison of three nihard i alloys conference osti. Table 1 the chemical compositions of different heats ic nihi nicr. F poissons ratio shear modulus youngs modulus poissons temperature ratio shear. Chapter 1 introduction, chapter 2 grey iron, chapter 3 spheroidal graphite cast iron, chapter 4 vermicular cast iron, and chapter 5 white cast iron. These alloys may be made by melting process and shall have microstructures that consist of carbides, martensite, bainite, austenite, and in exceptional cases, minor amounts of graphite or pearlite. Highstrength lowalloy steels include many standard and proprietary grades designed to provide specific desirable. The reader is cautioned that silicon and other alloying elements may considerably change the maximum solubility of carbon in austenite y.
Niresist d2 has good resistance to corrosion, corrosionerosion and frictional wear. Nihard is an extremely wear resistant material and in cast form is ideal for use with abrasive products, giving a much more extended life when compared with cast iron or mild steel when incorporated in pneumatic. Samples of each heat are analyzed prior to pouring to ensure exact chemical composition. Autonomous san luis potosi university, san luis potosi, mexico. From wikipedia, the free encyclopedia the society of automotive engineers sae designates sae steel grades. Influence of niobium and vanadium on the microstructure of. This book provides basic information covering every aspect of iron and steel production as well as a. Highchromium cast iron an overview sciencedirect topics. In comparison with hcci, it used to be thought that ni hard iron possessed similar abrasion resistance but lacked the impact resistance or blasting erosion resistance of hcci alloys 47. Nihard is the generic name for a family of white cast irons alloyed with nickel and chromium to give high hardness and outstanding resistance to abrasion. This specification deals with abrasionresistant cast irons used for mining, milling, earthhandling, and manufacturing industries. Applications are pumps, valves, compressors, turbocharger housings and exhaust gas manifolds used with niresist d2w, a primary ductile grade. Cast iron is a group of ironcarbon alloys with a carbon content greater than 2%.
By varying composition and heat treatment, these properties can be. Nihard abrasion resisting white irons bs 4844 1986. Here youll find current best sellers in books, new releases in books, deals in books, kindle. Therefore, in exceptional cases, alloys with less than 2 % c can solidify with a eutectic structure and therefore still belong to the family of cast iron.
The nickelchromium irons are also commonly identified as ni hard types 1 to 4. Keystock refers to barstock carefully drawn to ansi class 2 fits. Its important to note that only rexnord designs and manufactures all critical components used in our elevators. It increases the proof stress with also the tensile strength and hardness with no embrittlement in matrix. Metallurgical aspects of highchromium white irons prof. Nihard is an extremely wear resistant material and in cast form is ideal for use with abrasive products, giving a much more extended life when compared with cast iron or mild steel when incorporated in pneumatic conveying systems. Mastering photographic composition, creativity, and. Figures 1 and 2 show the relationship between tensile properties and hardness of rod and strip. Gray iron has a gray fracture surface with finely faced structure.
Designations, compositions and applications for six tool steels. China foundry publishes this book in several parts. Hard chrome is used as a wear resistant coating not only on steel but. Melting practice of nonferrous alloys of al, cu, mg, zn and ni, refining, deoxidation, degassing and grain refinement treatments. Chemical composition limits % of steel iron makes up the remaining percentage. Small quantities of chromium, nickel, molybdenum, copper, nitrogen, vanadium, niobium, titanium, and zirconium are used in various combinations.
Variations in the chromium to carbon ratio will provide fluctuating matrix structures from martensite to austenite. The ascast hardness is typically 500 bhn depending on the section thickness of the casting. The dominating factors are the chemical composition and the structure of the matrix. Here, the nickelchromium alloy composition has been adapted for chill casting and specialized sand casting processes. The composition of normal white cast iron is listed in table 51.
Words of blessing are written on red paper, called ch. Although ni hard cast iron and highchromium cast iron appeared almost at the same time, hcci was well developed in the 1960s and 1970s. The materials made of these alloys are used in metal working rolls, grinding mill liners, slurry pump parts, grinding media, pulveriser rings and more. Ni hard is the trade name for a group of nickel chromium alloyed white cast irons possessing outstanding resistance to abrasion. Pdf abstract the grades of nihard white cast iron alloys astma 532 are known as abrasion resistant. Mastering photographic composition, creativity, and personal style by alain briot. This is achieved by a balanced composition of carbon, nickel, chromium, silicon, and final heat treatment.
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