• attaining both small stratification and high performance is possible

... Products R.A Lula Consultant • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • W.C Mack Babcock & Wilcox Division McDermott Company T.P ... • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • R.D Forrest Division Fonderie Pechinery Electrometallurgie James Fox Charter Rolling Division ... Handbook The Volume was prepared under the direction of the ASM International Handbook Committee Authors and Reviewers • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • •...

Ngày tải lên: 10/08/2014, 12:21

... for CG irons: • • • • • • Lower coefficient of thermal expansion Higher thermal conductivity Better resistance to thermal shock Higher damping capacity Better castability, leading to higher casting ... solidification shrinkage is needed In other applications, however, malleable iron has a distinct advantage over ductile iron Malleable iron is preferred in the following applications: • • • • • Thin-section ... stem from their relative intermediate position between FG and SG irons Compared to FG irons, CG irons have certain advantages: • • • • • Higher tensile strength at the same carbon equivalent, which...

Ngày tải lên: 10/08/2014, 12:21

... "Specialty Steels and Heat-Resistant Alloys" in this Volume Classification of Steels Steels can be classified by a variety of different systems depending on: • • • • • • • • • The composition, ... hot-rolled bars The various mechanical and physical attributes implied by a quality descriptor arise from the combined effects of several factors, including: • • • • • • • The degree of internal soundess ... cooling is microalloyed medium-carbon steels (see Ref 36, 37 and the article "High- Strength Low-Alloy Steel Forgings" in this Volume) These steels contain small amounts of vanadium and niobium and...

Ngày tải lên: 10/08/2014, 12:21

... < = < = DIN standards JIS standards British standards AFNOR standards UNI standards Swedish standards References cited in this section Annual Statistical Report, International ... Stahlschlüssel (Key to Steel), References 1989 SAE Handbook, Materials, The Making, Shaping and Treating of Steel, 1989 SAE Handbook, Materials, Steels Heat Treatment and Processing Principals, The Physical ... Microstructure and Properties, Annual Statistical Report, Scr Metall., Proceedings of the Fifth International Conference on the Strength of Metals and Alloys, Encyclopedia of Materials Science and Engineering,...

Ngày tải lên: 10/08/2014, 12:21

... • • Turned and polished Turned, ground, and polished • • • Cold drawn, ground, and polished Cold drawn, turned, and polished Cold drawn, turned, ground, and polished Turning is done in special ... which are normally cold finished by cold rolling, or cold-drawn tubular products Cold-finished bars fall into five classifications: • • • • • Cold-drawn bars Turned and polished (after cold drawn ... designating sizes of structural shapes is as follows: • • • • • Beams and channels: By depth of cross section and weight per foot Angles: By length of legs and thickness in fractions of an inch...

Ngày tải lên: 10/08/2014, 12:21

... is another important mechanical property of steel springs However, this property is affected by many factors, and because of this complexity, fatigue is discussed in a separate section of this ... stainless is superior in corrosion resistance to type 302, particularly against pitting in salt water, but is more costly and is not considered a standard spring wire Type 302 is readily available and ... springs Both carbon and alloy steels are used extensively Steels for cold-wound springs differ from other constructional steels in four ways • • • • They are cold worked more extensively They are higher...

Ngày tải lên: 10/08/2014, 12:21

... to provide higher hardenability, increased wear resistance, higher impact resistance at increased strength, good machinability even at higher hardness, higher strength at elevated and low temperatures, ... Independent Integral and the Approximate Analysis of Strain Concentration by Notches and Cracks, J Appl Mech., Vol 35, June 1968, p 379 J.D Landes and D.H Shaffer, Statistical Characteristics of Fracture ... example, high- carbon steels: • • • Can carry somewhat higher contact stresses, such as those encountered in point contact loading in ball bearings Can be quenched and tempered, which is a simpler...

Ngày tải lên: 10/08/2014, 12:21

... 36 SAE/AISI 4340H UNS H43400 Heat-treating temperatures recommended by SAE Normalize (for forged or rolled specimens only): 870 °C (1600 °F) Austenitize: 845 °C (1550 °F) Figure 37 SAE/AISI E4340H ... 38 SAE/AISI 4620H UNS H46200 Heat-treating temperatures recommended by SAE Normalize (for forged or rolled specimens only): 925 °C (1700 °F) Austenitize: 925 °C (1700 °F) Figure 39 SAE/AISI 4626H ... 40 SAE/AISI 4718H UNS H47180 Heat-treating temperatures recommended by SAE Normalize (for forged or rolled specimens only): 925 °C (1700 °F) Austenitize: 925 °C (1700 °F) Figure 41 SAE/AISI 4720H...

Ngày tải lên: 10/08/2014, 12:21

... Numerous factors can contribute to cracking susceptibility (Ref 82, 83, 84, 85, 86, 87): • • • • • • • Carbon content Hardenability Ms temperature (the temperature at which martensite starts ... between hardened and nonhardened areas) References cited in this section 82 G.F Vander Voort, Failures of Tools and Dies, in Failure Analysis and Prevention, Vol 11, 9th ed., Metals Handbook, American ... from welding heat and the component is small enough, solution annealing will dissolve the precipitates and restore immunity However, in many cases this cannot be done because of distortion problems...

Ngày tải lên: 10/08/2014, 12:21

... low Highest 39-56 Medium to high High High Medium H11 Medium Deep Very low Highest 38-54 Medium to high Very high High Medium H12 Medium Deep Very low Highest 38-55 Medium to high Very high High ... Low Low High Highest A8 Medium Deep Lowest Highest 50-60 Medium High High Medium to high A9 Medium Deep Lowest Highest 35-56 Medium High High Medium to high A10 Medium to high Deep Lowest Highest ... medium High 36-54 Medium High High Medium to high H22 Medium Deep A, low; O, medium High 39-52 Medium High High Medium to high H23 Medium Deep Medium High 34-47 Medium Medium Very high Medium to high...

Ngày tải lên: 10/08/2014, 12:21

... produce sound forged components, the forging tooling must be designed to take into account: • • • • • • • • • Preform temperature Die temperature Forging pressure The elastic strain of the die The ... both within individual grains and along grain boundaries This tendency is aggravated by higher P levels (>0.05%), higher pouring temperatures (which promote segregation in the casting), and higher ... Chromium enhances resistance to both atmospheric corrosion and abrasion, although the latter effect is not always consistent and depends on the individual application It is also used up to 18%...

Ngày tải lên: 10/08/2014, 12:21

... diminishing chromium and molybdenum segregation, and raising the corrosion resistance of the austenitic phase Nitrogen is highly detrimental to the mechanical properties of the ferritic grades and ... application as orthopedic implants Material is required that is capable of moderately high strength and resistance to wear and fretting corrosion and to pitting and crevice attack Vacuum-melted type ... is a critical pitting temperature for a particular environment, there is a critical crevice temperature This temperature is specific to the geometry and nature of the crevice and to the precise...

Ngày tải lên: 10/08/2014, 12:21

... growth and mass transport within the liquid toward the liquid/vacuum interface is dependent on: • • • • • • The quantity of the dissolved gas The decreased pressure exerted on the bubble as it rises ... include: • • • • • • • Intermetallic phase precipitation (σ, μ, Laves) Phasial decomposition (carbides, borides, nitrides) Phase coalescence and coarsening (γ') Phasial solutioning and reprecipitation ... affects not only the yield and cost of components but also the defect level and therefore component performance Single-crystal casting defects of concern are: • • • • • • Freckling: A spiral of...

Ngày tải lên: 10/08/2014, 12:21

... gray and ductile irons are dealt with in the articles "Gray Iron" and "Ductile Iron" in this Volume This article discusses abrasion-resistant chilled and white irons, high- alloy corrosion-resistant ... nodular in both form and distribution of carbon Heat-resistant irons combine resistance to high- temperature oxidation and scaling with resistance to softening or microstructural degradation Resistance ... respectively Otherwise, ferritic iron produced from two-stage annealing is reheated to the austenite temperature and then quenched This method is discussed in the section "Rehardened -and- Tempered Malleable...

Ngày tải lên: 13/08/2014, 05:21

... incorporate AISI-SAE designations A 29 Carbon and alloy steel bars, hot rolled and cold finished A 108 Standard quality cold-finished carbon steel bars A 295 High carbon-chromium ball and roller ... will provide information about the items listed below: • • • • • Scope may cover product classification, including size range when necessary, condition, and any comments on product processing deemed ... steel products publish standard specifications, many of which have become well known and highly respected Some of the important specification-writing groups are listed below It is obvious from the...

Ngày tải lên: 13/08/2014, 05:21

... Carbon and Low-Alloy Steels" and "High- Strength Structural and High- Strength Low-Alloy Steels" in this Volume Table Composition ranges and limits for AISI-SAE standard low-alloy steel plate applicable ... or 5.84 mm in.) and greater across • • (0.230 in.) and greater in thickness and 203 mm (8 in.) and less in width Small angles, channels, tees, and other standard shapes less than 76 mm (3 in.) ... of both the semifinished and the finished product and either subsequent removal of the defects or rejection of the material if defect removal is not possible Inspection techniques range from visual...

Ngày tải lên: 13/08/2014, 05:21

... listing of over 600 HSLA steels in Ref 23), HSLA steels can be divided into six categories: • • • • • • • Weathering steels, which contain small amounts of alloying elements such as copper and ... that is due to the presence of vanadium, niobium, and titanium The various types of microalloyed ferrite-pearlite steels include: • • • • • • • • Vanadium-microalloyed steels Niobium-microalloyed ... HSLA steels and product forms These processing methods include: • • • • • The controlled rolling of precipitation-strengthened HSLA steels to obtain fine austenite grains and/ or highly deformed...

Ngày tải lên: 13/08/2014, 05:21

... Handbook, Society of Automotive Engineers, 1989 10 11 12 13 14 Hardenability of Carbon and Low-Alloy Steels Revised by Harold Burrier, Jr., The Timken Company Selected References • • • • • • • ... ways listed below and illustrated in Fig 1: • The minimum and maximum hardness values at any desired distance This method is illustrated as points A-A and is specified as J43 to J54 = • 16 in ... hardenability This is true to a degree, but several factors weigh against the use of large amounts of carbon: • • • • High carbon content generally decreases toughness at room and subzero temperatures...

Ngày tải lên: 13/08/2014, 05:21