Titanium CP Grade 4 / AMS-T-9046 CP1 / AMS 4901

Technical Data Sheet

Chemical Composition Limits

Weight %







Titanium CP Grade 4







Titanium Grades 1-4 are unalloyed and generally known as CP (Commercially Pure). The tensile and yield strength of titanium generally increases with the grade number. Titanium is 30% stronger than Steel but nearly 50% lighter and although Aluminium is lighter, Titanium is stronger and has excellent strength retention. Due to Titanium's weight, strength and high corrosion resistance it is very popular in various manufacturing industries from aerospace, medical, shipping, military etc.

Typical Mechanical Properties


Tensile Strength min

Yield Strength

Elongation (%)





Titanium CP Grade 4
Annealed Sheet






as per MIL-T-9046J, AMS-T-9046, AMS 4901

BS 3TA6 - Sheet, strip
BS 3TA7 - Bar
BS 2TA8 - Forging stock

AMS 4901 - Sheet, strip, plate
AMS 4921 - Bar
AMS-T-9046B - Sheet, strip, plate
AMS-T-9047A CP70 - Bar
MIL-T-9046H Type 1 Comp B - Sheet, strip, plate
MIL-T-9046J CP1 - Sheet, strip, plate
MIL-T-9074G CP70 - Bar

ASTM B265 - Gr4 Sheet, plate
ASTM B337 - Gr4 Pipe (withdrawn)
ASTM B338 - Gr4 heat exchanger tube
ASTM B348 - Gr4 bar
ASTM B367 - Gr4 castings
ASTM B381 - Gr4 forgings
ASTM F67 - Gr4 Surgical Implant
ASTM F467 - Gr4 nuts
ASTM F468 - Gr4 bolts

Werkstoff WS3.7064 (aerospace)
Werkstoff WS3.7065
LN 9297


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CP Titanium Grade 4



Type Analysis

Single figures are nominal except where noted.

Carbon (Maximum)






Nitrogen (Maximum)



Iron (Maximum)



Oxygen (Maximum)



Hydrogen (Maximum)



Other, Total (Maximum)






ASTM B 348-99, "Other, Total" = 0.40% maximum and AMS 4921 rev. G = 0.3% maximum.


General Information


Pure titanium undergoes an allotropic transformation from the hexagonal close-packed alpha phase to the body-centered cubic beta phase at a temperature of 882.5ºC (1620.5ºF).

Commercially pure, or CP, titanium is unalloyed. At service temperatures it consists of 100% hcp alpha phase. As a single-phase material, its properties are controlled by chemistry (iron and interstitial impurity elements) and grain size. CP Titanium is classified into Grades 1 through 4 depending on strength and allowable levels of the elements iron, carbon, nitrogen, and oxygen. CP Ti Grade 4 is the strongest of these grades, with a minimum yield strength of 480 MPa (70 ksi), and has the highest allowable oxygen and iron content of the grades.

Grade 4 combines the excellent resistance to corrosion and corrosion fatigue of titanium with high strength that makes it a candidate to compete with steels and nickel alloys for many chemical and marine applications.


CP Titanium Grade 4 could be considered in any application where strength and corrosion resistance are important. Grade 4 also has good ductility, is moderately formable, and has superior corrosion fatigue resistance in seawater. Applicable service temperatures for CP Ti Grade 4 are up to 204ºC (400ºF).

Some applications have included airframe and aircraft engine components, marine and chemical processing machinery, heat exchangers, reaction vessels for chemical processing and desalinization plants, corrosive waste disposal wells, and pulp and paper production.



Corrosion Resistance

The corrosion resistance of CP Ti Grade 4 is based on the presence of a stable, continuous, tightly adherent oxide layer which forms spontaneously upon exposure to oxygen. If damaged, it re-forms readily as long as there is some source of oxygen (air or moisture) in the environment. CP Ti Grade 4 has outstanding resistance to corrosion fatigue in marine environments. In seawater, it is fully resistant to corrosion at temperatures up to 315ºC (600ºF). The possibility of crevice corrosion must be considered, however, and components appropriately designed to avoid tight crevices.

CP Ti Grade 4 is highly resistant to many chemical environments including oxidizing media, alkaline media, organic compounds and acids, aqueous salt solutions, and wet or dry hot gases. It also has sufficient corrosion resistance in liquid metals, nitric acid, mildly reducing acids, and wet chlorine or bromine gas (as long as a minimal amount of oxygen or water is present).

Conditions under which CP Ti Grade 4 is susceptible to corrosion are strongly reducing acids, alkaline peroxide solutions, and molten chloride salts. Crevice corrosion can occur in hot halide or sulfate solutions (>1000ppm at 75ºC or higher), which is a consideration in marine applications.

CP Ti Grade 4 is resistant to stress-corrosion cracking (SCC) in aqueous solutions, and is largely resistant to SCC in general. Conditions under which CP Ti Grade 4 is susceptible to SCC include anhydrous methanol, methanol/halide solutions, nitrogen tetroxide, and in contact with liquid or solid cadmium or liquid mercury.

CP Grade 4 titanium is susceptible to hydrogen embrittlement due to the formation of hydrides. Specifications for CP Ti Grade 4 mill products typically specify a maximum hydrogen limit of 150 ppm, but it is possible for degradation to occur at lower levels, especially in the presence of a notch. The presence of a notch or other stress raiser increases the detrimental effect, as hydrogen migrates to the notch area, raising the local concentration of hydrides. It is important to minimize hydrogen pickup during processing, particularly heat treating and acid pickling.

Important Note:The following 4-level rating scale is intended for comparative purposes only. Corrosion testing is recommended; factors which affect corrosion resistance include temperature, concentration, pH, impurities, aeration, velocity, crevices, deposits, metallurgical condition, stress, surface finish and dissimilar metal contact.

Sulfuric Acid


Acetic Acid


Sodium Hydroxide


Salt Spray (NaCl)


Sea Water




·  General Corrosion Rates in Various Media



Physical Properties





Mean Specific Heat




·  Thermal Conductivity Graph

Modulus of Elasticity (E)



x 103 ksi 

Beta Transus


1715 to 1765


Alpha Transus


1635 to 1685


Liquidus Temperature


3000 to 3040


Electrical Resistivity




·  Thermal Expansion Graph

Magnetic Properties

Magnetic Attraction

·  None


Typical Mechanical Properties

CP Ti Grade 4 has the highest strength of the CP grades, making it competitive with stainless steels for many corrosion resistant applications. Its strength is on a par with annealed stainless steels, and, in addition, it offers lighter weight and superior corrosion resistance. CP Grade 4 titanium is not subject to grain boundary embrittlement or sensitization at elevated temperatures. Specific strength (strength/density) provides a way to compare materials based on a combination of strength and weight.

·  Charpy V-Notch Impact Toughness vs. Temperature

·  Elevated Temperature Mechanical Properties

·  Fatigue Limits

·  Room Temperature Mechanical Properties

·  Strength and Specific Strength

·  Typical Room Temperature Strengths


CP Ti is very ductile and tough. Because of its high toughness and low strength, standard plane-strain fracture toughness testing (K 1c ) is impractical for CP Ti. Notched impact (Charpy) testing is generally used to evaluate toughness.



Heat Treatment

Heat treatments used for CP Ti are annealing and stress relieving. Annealing is used to fully soften the material and remove all residual stresses. Annealing of wrought products at typical temperatures (below the beta transus) results in a fully recrystallized equiaxed alpha structure. Precise control of grain size (and mechanical properties) can be achieved by adjusting the anneal temperature.

Stress relieving is used to remove some or most of the residual stresses from forming, or to recover compressive yield strength after stretching.

Titanium and its alloys have a high affinity for gases including oxygen, nitrogen and hydrogen. When CP Ti is heated in air, oxygen absorption results in the formation of an extremely hard, brittle oxygen-stablized alpha phase layer known as alpha case.

Intermediate and final annealing of CP Ti is often performed in a vacuum or inert gas atmosphere to avoid alpha case formation and the associated material loss. Vacuum annealing can also be used to remove excess hydrogen pickup, a process known as vacuum degassing. Parts to be vacuum heat treated must be thoroughly cleaned (see Cleaning Notes).

·  Typical Heat Treatments



Hot Working

CP Ti Grade 4 can be processed by conventional techniques such as hot rolling, forging, and hot pressing. Temperatures for initial roughing may be as high as 30-50ºC (50-100ºF) above the beta transus, and temperatures for finish processing are typically in the alpha/beta phase field, ranging from about 815ºC (1500ºF) to about 900ºC (1650ºF).

CP Ti Grade 4 can be formed into finished parts by standard methods such as forging, spin forming, hydroforming, and hot pressing. Typically, more severe forming is done in the temperature range of 480-540ºC (900-1000ºF) and milder forming from 200-315ºC (400-600ºF). Care must be taken to prevent the formation of excessive alpha case, and alpha case must be removed after processing.

Cold Working

CP Ti Grade 4 has relatively good ductility and can be formed at room temperature, although cold forming deformation must be less severe than for the lower-strength grades. Standard methods, including bending, stretch forming, heading, stamping, and drawing, are applicable to CP Ti Grade 4. CP Ti work hardens fairly rapidly, which is a limitation in some operations, such as cold drawing. The Bauschinger effect results in a drop of up to 25% in compressive yield strength upon stretching at room temperature; this drop can be recovered by stress relieving. Due to the low modulus of titanium, springback allowances are significant. Hot sizing after cold forming is often used to correct for variations in springback.


The machining characteristics of CP Ti Grade 4 are similar to those of austenitic stainless steels. In general, low cutting speeds, heavy feed rates, and copious amounts of cutting fluid are recommended. Sharp tools and rigid setups are also important. Because of the strong tendency of titanium to gall and smear, feeding should never be stopped while the tool and workpiece are in moving contact. Non-chlorinated cutting fluids are generally used to eliminate any possibility of chloride-induced stress-corrosion cracking. It should be noted that titanium chips are highly combustible and appropriate safety precautions are necessary.

Following are typical feeds and speeds for CP Ti Grade 4.

·  Machinability Tables

·  Typical Minimum Stock Removal Requirements


CP Ti Grade 4 can be welded using CP Ti filler metal. Inert gas shielding techniques must be employed to prevent oxygen pickup and embrittlement in the weld area. Gas tungsten arc welding is the most common welding process for CP Ti. Gas metal arc welding is used for thick sections. Plasma arc welding, spot welding, electron beam, laser beam, resistance welding and diffusion welding have all been used successfully in CP Ti welding applications.



Other Information

Wear Resistance

Commercially pure Ti and its alloys have a tendency to gall and are not recommended for wear applications.

Descaling (Cleaning)

Following heat treatment in air, it is extremely important to completely remove not only the surface scale, but the underlying layer of brittle alpha case as well. This removal can be accomplished by mechanical methods such as grinding or machining, or by descaling (using molten salt or abrasive) followed by pickling in a nitric/hydroflouric acid mixture.

Titanium is also susceptible to hydrogen embrittlement, and care must be taken to avoid excessive hydrogen pickup during heat treating and pickling/ chemical milling.

Final heat treatments on finished parts must be performed in vacuum if machining or pickling is to be avoided.

The cleanliness of parts to be vacuum heat treated is of prime importance. Oils, fingerprints, or residues remaining on the surface can result in alpha case formation, even in the vacuum atmosphere. In addition, chlorides found in some cleaning agents have been associated with SCC of titanium alloys. Parts to be vacuum heat treated should be processed as follows: thorough cleaning using a non-chlorinated solvent or aqueous cleaning solution, followed by rinsing with copious quantities of deionized or distilled (not regular tap) water to remove all traces of cleaning agent, and finally, drying. Following cleaning, parts must be handled with clean gloves to prevent recontamination of the surface.

Applicable Specifications

·  AMS 4901 (Sheet, Strip, Plate)

·  AMS 4921 (Bar, Wire, Forgings, Billet)

·  ASTM B 381 (Forgings)

·  ASTM B265 (Sheet, Strip, Plate)

·  ASTM B348 (Bar, Billet)

·  ASTM B367 (Castings)

·  ASTM F 1341 (Wire)

·  ASTM F 67 (Sheet, Strip, Bar)

·  ISO 5832-2

·  MIL-T 9047 (Bars, Billets)













TITANIUM GR4 Tube / Pipe








TITANIUM GR4 Coil /Strap






TITANIUM GR4 Fasteners / Flanges


TITANIUM GR4 Welding Product



Every effort is made to ensure that technical specifications are accurate. However, technical specifications included herein should be used as a guideline only. All specifications are subject to change without notice.

Provide all grade of these alloy by different shape & size is Our expertise

For any inquiry & request, don't hesitate to contact us