ATI Datalloy HP TM Alloy

Transcription

1 ATI Datalloy HP TM Alloy UNS N08830 INTRODUCTION ATI Datalloy HP TM alloy is a Ni-Cr-Mo-Fe non-magnetic high strength alloy with exceptional pitting and crevice corrosion resistance, while maintaining excellent toughness and wear resistance. This material has improved microstructural stability as compared to other grades similar in corrosion resistance, allowing for greater reliability and manufacturing productivity. ATI Datalloy HP alloy has been developed to meet the increasing demands of the Drilling & Measurement market segment in such products as Rotary Steerable components, MWD/LWD Collars, Housings and Internals and non-magnetic Drill Collars, Stabilizers and Drill Pipe. Drilling and Measurement tubulars are used to contain sensitive instrumentation which helps control the direction of a drill string during the drilling of oil and gas wells. Technology advances and more onerous drilling environments have demanded the need for materials that can perform in high-temperature, high-pressure, corrosive environments and ATI Datalloy HP alloy offers these features without decrementing the other key characteristics required by the Industry. The alloy has desirable properties for many other applications in the Oil and Gas sector, including but not limited to Completion equipment, Subsea and Wellhead components. ATI Datalloy HP TM alloy complies, as a minimum, with the mechanical property requirements of API 7-1, and is undergoing sour service testing in compliance with NACE MRO175 / ISO STRUCTURE ATI Datalloy HP TM alloy maintains excellent phase stability with a homogeneous, low-segregation, ultra-clean structure and has a maximum relative magnetic permeability of Controlled thermo-mechanical processing generates the material s mechanical properties. ATI Datalloy HP TM alloy cannot be hardened by heat treatment. CHEMICAL PROPERTIES Composition Range (UNS N08830) Element Wt. % Element Wt. % Carbon Manganese Phosphorous Sulfur Silicon 1.00 Nickel Chromium Molybdenum Copper Cobalt Tungsten Nitrogen Iron balance Maximum % unless a range is indicated. VERSION 1 (4/14/2015): PAGE 1 of 6

2 PHYSICAL PROPERTIES Typical Physical Properties Modulus of Elasticity 30.4 x 10 6 psi 210 GPa Poisson s Ratio Coefficient of Thermal Expansion* 8.30 x 10 6 in/in/ F µm/m/k Resistivity µω in µω cm Thermal Conductivity 5.87 BTU/hr-ft- F W/cmK Density lb/in gcm 3 Relative Magnetic Permeability max max. Specific Heat 0.11 BTU/lb- F 460 J/kgK Thermal Diffusivity 0.11 ft 2 /hr x 10-5 m 2 /sec * Temperature range 68 F 400 F (20 C C) MECHANICAL PROPERTIES ATI Datalloy HP TM Alloy Mid-Radius Up to 8.5 (216 mm) in Diameter RT RT F (175 C) RT After 2100 F (1149 C) Anneal 0.2% Yield Strength 150 ksi (1035 MPa) ksi (1135 MPa) 158 ksi (1086 MPa) 140 ksi (965 MPa) 125 ksi (861 MPa) (¼ inch plate) 64 ksi (441 MPa) 64 ksi (441 MPa) UTS 170 ksi (1170 MPa) 180 ksi (1240 MPa) 176 ksi (1212 MPa) 150 ksi (1035 MPa) 140 ksi (966 MPa) (¼ inch plate) 123 ksi (848 MPa) 120 ksi (827 MPa) Elongation 20% 23% 20% 20% 21% 57% 60% Toughness, RT 110 ft-lb (150 J) 160 ft-lb (217 J) 143 ft-lb (194 J) (1 inch plate) 295 ft-lb (400 J) Toughness -75 F (-60 C) 145 ft-lb (197 J) 79 ft-lb (107 J) Hardness, HRC 45 max. 41 VERSION 1 (4/14/2015): PAGE 2 of 6

3 FATIGUE Fatigue testing was performed using a Wöhler rotating bend test configuration, tested at 4000 cycles per minute. ATI Datalloy HP TM Alloy Rotating Beam Fatigue Typical Behavior In rotating bend Wöhler-type fatigue tests, high-strength ATI Datalloy HP TM alloy with 0.2% yield strengths in excess of 140 ksi, has been shown to have a fatigue endurance limit in excess of 60 ksi. CORROSION The localized corrosion resistance of ATI Datalloy HP TM alloy has been tested per ASTM G48. The critical pitting temperature (CPT) has been determined to be a minimum of 75 C per ASTM G48 Method C. The critical crevice temperature (CCT) is 35 C per ASTM G48 Method D. Alloys commonly used for drill string components have much less localized corrosion resistance as shown in the figures below. In ASTM G48 Method C testing at 50 C, ATI Datalloy HP TM alloy is immune to corrosion, whereas Alloys 718 and 925 suffer significant material loss. A similar trend is observed in crevice corrosion testing at 20 C. ATI Datalloy HP TM alloy even demonstrates superior crevice corrosion when compared to Alloy 625 at 35 C. Stress Corrosion Cracking (SCC) has been evaluated using u-bend specimens immersed in boiling acidified 25% NaCl (ASTM G123) and boiling 33% LiCl. No cracking occurred during 1000 hours of exposure in both conditions. VERSION 1 (4/14/2015): PAGE 3 of 6

4 Pitting Corrosion ASTM G48C Acidified FeCl 3 Crevice Corrosion ASTM G48D Acidified FeCl 3 CPT = 75ºC min. CCT = 35ºC min. Pitting Comparison 50ºC Crevice Corrosion Comparison 20ºC API 718 Aged 925 Aged Datalloy HP TM API 718 Aged 925 Aged Datalloy HP TM MACHINABILITY Austenitic alloys have unique properties that give them different machinability characteristics as compared to carbon steel or ferritic, duplex or martensitic stainless steels. The greatest difference is the higher ductility of austenitic alloys as well as their tendency to work harden and form built-up edges on the cutting tool. Super-austenitic alloys have a machinability rating of around 40% that of standard ferritic stainless steels. They also have a very high tendency to work harden during machining. As such, around a third of the tool life typical when machining ferritic grades can be achieved. Super austenitic alloys are very ductile when compared to carbon and low alloy steels, so chip formation is far more difficult. Austenitic grades also work harden much more readily. These properties mean that cutting angle should be very positive and tools should not be allowed to dwell on the surface. The figures below are recommended for a tip life providing a 45- minute tool life at 75 meters/min. Turning Operations Tool Grade Cutting Geometry Roughing* SMNG SM GC1105 Depth of Cut 3 mm in Cutting Speed Range m ft Feed (mm/rev) 0.25 mm/rev in/rev Semi Finishing CNMG SF S05F 1mm in m ft 0.15 mm/rev in/rev * 45 degree approach angle VERSION 1 (4/14/2015): PAGE 4 of 6

5 A machinability study by ATI shows that an 8 50 micron finish can be attained at speeds 30% faster than the maximum speeds of other ATI alloys. The theoretical value of the Ra is calculated as: Ra = (50 x feed^2) / Radius = 2.5 mm or 0.1 inch. The curves are under this value and show a correct cutting action from the insert geometry. VERSION 1 (4/14/2015): PAGE 5 of 6

6 GALLING RESISTANCE Galling in the oil industry is defined as the seizure of, and damage to, threaded connections on tightening or untightening. Tests performed by ATI have shown that the intrinsic galling resistance of Datalloy HP TM alloy is superior to that of Alloy 718 in the fully hardened condition. WELDABILITY Good welding procedures using C22 filler metal are appropriate to maintain corrosion resistance. Hard coating practices are possible using similar procedures as are used for hard coating other non-magnetic grades. CONTACT INFORMATION For further assistance on ATI Datalloy HP TM alloy, please contact ATI Specialty Materials at in the United States or in the United Kingdom or visit our website at. VERSION 1 (4/14/2015): PAGE 6 of 6