ML20151S165

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Testing of 11 Bolts
ML20151S165
Person / Time
Site: Farley  Southern Nuclear icon.png
Issue date: 10/30/1987
From: Czajkowski C
BROOKHAVEN NATIONAL LABORATORY
To:
Shared Package
ML20151S130 List:
References
NUDOCS 8804280217
Download: ML20151S165 (29)
v • d • e


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TESTING OF 11 BOLTS C. Czajkowski October 30, 1987-Brookhaven National Laboratory Department of Nuclear Energy Nuclear Waste & Technclogy Civision i

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r BOLT IDENTIFICATION: 50-18 BOLT SPECIFICATION: A 193-87 BOLT SIZE: 3/4 - 10 UNC TENSILE STRENGTH:

Actual Required by Specification 142.22 ksi 125 ksi (min.)

Failure Location - Threads HARD!'ESS:

Actual Required by Specification 59.16 R Not Required A ,

. CHEMICAL ANALYSIS:

Actual w/o Requirdd by Specification w/o l

l Carbon 0.34 0.37 - 0.49 Manganese 0.96 0.65 - 1.10 Phosphorus 0.12 0.035 max Sulfur 0.006 0.040 max I Silicon 0.28 0.15 - 0.35 l Chronium 1.55 (Note 1) 0.75 - 1.20 l Nickel 0.06 -

tiolybdenun 0.19 0.15 - 0.25 Vanadiun <0.05 -

l Colnnbium + Tantalum <0.05 -

< = Less than COMMENTS: 1) Chroniun valte exceeds specification requirements even factoring hpemissible variations (0.05% over) l l

BOLT IDENTIFICATION: S0-19 BOLT SPECIFICATION: A 193-B7 BOLT SIZE: 1" - 8 UNC TENSILE STRENGTH:

Actual Required by Specification 143.03 ksi 125 ksi (min.)

Failure Location - Shoulder HARDNESS:

Actual Required by Specification 27.6 R Not Required c

CHEMICAL XMALYSIS:

Actual w/o Reauired by Specification w/o l Carbon 0.40 0.37 - 0.49 flanganese 0.98 0.65 - 1.10 Phosphorus 0.005 0.035 asx Sulfur 0.016 0.040 max Silicon 0.21 0.15 - 0.35 Ch ronium 1.80 (Note 1) 0.75 - 1.20 Nickel 0.34 -

liolybdenun 0.19 0.15 - 0.25 Vanadiun . <0.05 -

Columbium + Tantalun <0.05 -

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COMMENTS: 1) Chronium value exceeds specification requirenents even factoring l

in permissible variations (0.05% over)

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BOLT IDENTIFICATION: S0-20 BOLT SPECIFICATION: A 193-B7 BOLT SIZE: 3/8" - 16 UNC TENSILE STRENGTH:

Actual Required by Specification 151.74 ksi 125 ksi (min.)

Failure Location - Threads HARDNESS:

Actual Required by Specification 23.83 R Not Required c .

~% CHEMICAL ANALYSIS:

Actual w/o Required by Specification w/o Carbon 0.41 0.37 - 0.49 Manganese 0.97 0.65 - 1.10 Phosphorus <0.005 0.035 nax Sulfur 0.008 0.040 max Silicon 0.27 0.15 0.35 Ch romium 1.51 (Note 1) 0.75 - 1.20 Nickel 0.05 -

flolybdenum 0.22 0.15 - 0.25 Vanadiun <0.05 -

Columbiun + Tantalun <0.05 -

< = Less than COMMENTS: 1) Chromium value exceeds specification requirements even factoring in permissible variations (0.05% over) t

BOLT IDENTIFICATION: S0-21 BOLT SPECIFICATION: A 193-87 BOLT SIZE: 1/4" - 20 UNC TENSILE STRENGTH:

Actual Required by Specification 158.80 ksi 125 ksi (min.)

Failure Location - Threads HARDNESS:

Actual Reauired by Specification 62.6 R A Not Required

\ CPEMICAL ANALYSIS:

Actual w/o Reauired by Specification w/o Carbon 0.41 0.37 - 0.49 tianganese 0.94 0.65 - 1.10 Phosphorus 0.020 0.035 nax Sulfur 0.024 0.040 nax Silicon 0.27 0.15 - 0.35 l Chronium 1.46 (Note 1) 0.75 - 1.20 L Nickel 0.47 -

l 11olybdenun 0.23 0.15 - 0.25 Vanadiun <0.05 -

Colunbium + Tantalun <0.05 -

< = Less than l COMMENTS: 1) Chroniun value exceeds specification requirements even factoring in permissible variations (0.05% over) i

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BOLT IDENTIFICATION: 50-22 BOLT SPECIFICATION: A 193-88 BOLT SIZE: 5/8" - 11 UNC TENSILE STRENGTH:

Actual Required by Specification 98.14 ksi 75 ksi (min.)

Failure Location - Threads HARDNESS:

Actual Required by Specification 47 R 223HB(max.)

A (equates to 138 HB) i~

CHEMICAL ANALYSIS:

Actual w/o Required by Specification w/o Carbon 0.06 0.08 max Manganese 1.24 2.00 max Phosphorus 0.030 0.045 max Sulfur' O.033 (Note 1) 0.030 max

Silicon 0.40 1.00 max

, Chromium 19.1 18.00 - 20.00 l Nickel 8.8 8.00 - 10.50

tiolybdenur 0.36 -

Vanadium <0.05 -

Columbium + Tantalum <0.05 -

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< = less than COMMENTS: 1) Permissible variation for sulfur (0.005% over) by specification l

l allows acceptance of this value.

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. BOLT IDENTIFICATION: S0-23 BOLT SPECIFICATION: A 193-88 BOLT SIZE: 5/8" - 11 UNC TENSILE STRENGTH:

Actual Required by Specification 89.65 ksi 75 ksi (min.)

Failure Location - Threads HARDNESS:

Actual Required by Specification 63.6 RA (Note 1) 223 HB (max.)

(equates to 262 HB)

CHEMICAL ANALYSIS: -

Actual w/o Required by Specification w/o Carbon 0.06 0.08 max flanganese 1.75 2.00 max Phosphorus 0.050 (Note 1) 0.045 max Sulfur 0.021 0.030 max Silicon 0.72 1.00 max Chromium 19.0 18.00 - 20.00 Nickel 9.0 8.00 - 10.50 llolybdenun 0.40 -

Vanadium <0.05 -

Columbium + Tantalum <0.0S -

< = Less than 1 .

COMMENTS: 1) Althouoh specification allows a maximum hardness of 241 HB (A193), this bolt exceeds hardness naxinum. 2) Pernissible variation for phosphorus (0.010% over) by specification allows acceptance of this value.

BOLT IDENTIFICATION: 50-24 BOLT SPECIFICATION: A 193-B8 BOLT SIZE: 5/8" - 11 UNC TENSILE STRENGTH:

Actual Required by Specific 3 tion 89.91 ksi 75 ksi (min.)

Failure Location - Threads HARONESS:

Actual Required by Specification 61.3 RA (flote 1) 223 HB (max.)

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(equates to 234 HB)

N CHEMICAL ANALYSIS:

Actual w/o Required by Specification w/o l Carbon 0.05 0.08 max l

Manganese 1.70 2.00 max l

Phosphorus 0.020 0.045 max Sulfur 0.025 0.030 max Silicon 0.70 1.00 max l Chromium 19.3 18.00 - 20.00 l Nickel 9.0 8.C 0 - 10.50 l tiolybdenum 0.42 -

l Vanadi um < 0.0 5 -

Columbium + Tantalum <0.05 -

< = Less than COMMENTS: 1) For bolt sizes 3/4 in. diameter and under, a maximum hardness of 241 HB is pemitted (A193).

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.. BOLT IDENTIFICATION: S0-25 BOLT SPECIFICATION: A 193-B8 BOLT SIZE: 1/4" -'20 UNC TENSILE STRENGTH:

Actual Required by Specification 114.46 ksi 75 ksi (min.)

Failure Location - Threads HARDNESS:

Actual Required by Specification 57.7 R 223 HB (max.)

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(equates to 167 HB)

's CHEMICAL ANALYSIS:

Actual w/o Required by Specification w/o Carbon 0.09 (Note 1) 0.08 max Manganese 0.57 Phosphorus 0.050 (Note 1) 0.045 max l

Sulfur 0.021 0.030 max I

Silicon 0.43 1.00 max Chromiun 19.3 18.00 - 20.00 1 Nickel 9.5 8.00 - 10.50 I

liolybdenum -

0.36 -

l Vanadium <0.05 -

l Columbium + Tantalun <0.05 -

< = Less than COMMENTS: 1) Permissible variations,for both carbon (0.01% over) and 1

! phosphorus (0.010% over) by specification allows acceptance of these values.

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9 BOLT IDENTIFICATION: 50-26 BOLT SPECIFICATION: A 325

, BOLT SIZE: 1/2" - 13 UNC TENSILE STRENGTH:

Actual Required by Specification 144.3 ksi 120 ksi (min.)

Failure location - Threads HARDNESS:

Actual Required by Specification 24.75 R c .

24 Rc min - 35 Rc nax (equates to 167 HB)

CHEMICAL ANALYSIS:

Actual w/o Required by Specification w/o Carbon 0.33 0.27 min (Product) flanganese 0.86 0.47 min (Product)

Phosphorus 0.008 0.048 max (Product) l Sulfur 0.013 0.058 max (Product)

Silicon 0.29 -

l Lhronium 0.08 -

Nickel 0.06 -

Molybdenun <0.01 -

Vanadi um <0.05 -

Columbiun + Tantalun <0.05 -

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< = Less than COMMENTS: 1) Meets chemical requirements for Type 1 bolts.

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BOLT IDENTIFICATION: 50-27 BOLT SPECIFICATION: A 325 BOLT SIZE: 1/2" - 13 UNC

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TENSILE STRENGTH:

Actual Requirsd by Specification 133.17 ksi 120 ksi (min.)

Failure location - Threads HARDNESS:

Actual Required by Specification 21.25 Rc (Note 1) 24 R min - 35 R cmax CHEMICAL ANALYSIS:

Actual w/o Required by Specification w/o Carbon 0.42 (tote 2) 0.27 min (Product) tianganese 0.88 0.47 min (Product)

Phosphorus 0.005 0.048 max (Product)

Sulfur 0.025 0.058 max (Product)

Silicon 0.17 -

Chromium <0.01 -

Nickel 0.08 -

tiolybdenum <0.01 -

Vanadium <0.05 -

Columbiun + Tantalum <0.05 -

< = Less than C0f tMENTS: 1) For bolts where both tensile and hardness tests are perforned, acceptance shall be based on tensile results (in event of low hardness readinos) - A 325. 2) tieets chemical requirements for Type 1 bolts.

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BOLT IDENTIFICATION: S0-28 BOLT SPECIFICATION: A 325 80LT SIZE: 1/2" - 13 UNC TENSILE STRENGTH:

Actual _

Required by Specification 141.48 ksi 120 ksi (min.)

Failure Location - Threads HARDNESS:

Actual Required by Specification 22 Rc (N te 1) 24 Rc min - 35 R cmax i CHEMICAL ANALYSIS:

Actual w/o Required by Specification w/o Carbon 0.40 (Note 2) 0.27 min (Product)

Hanganese 0.85 0.47 min (Product)

Phosphorus <0.005 0.048 nax (Product)

Sulfur 0.020 O.058 max (Product)

Silicon 0.21 -

Chromium <0.01 -

Nickel 0.10 -

Molybdenum <0.01 -

l~ Vanadium <0.05 -

Columbiun + Tantalum <0.05 -

< = Less than COMMENTS: 1) For bolts where both tensile and hardness tests are performed, acceptance shall be based on tensile results (in event of low hardness readings) - A 325. 2) Meets chenical requirements for Type 1 bolts.

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BOLT IDENTIFICATION: S0-18 BOLT SPECIFICATION: A193-87 BOLT SIZE: 3/4 - 10 UNC TENSILE STRENGTH:

Actual Required by Specification 142.22 ksi 125 ksi (min.)

Failure Location - Threads HARDNESS:

Actual Required by Specification 59.16 R A Not Requir?d CHEMICAL ANALYSIS:

Actual w/o Required by Specification w/o i

Carbon 0.34 (Note 2) 0.37 - 0.49 Hanganese 0.96 0.65 - 1.10 Phosphorus 0.12 0.035 max

, Sulfur 0.0 06 0.040 max l Silicon 0.28 0.15 - 0.35

CF romium 1.55 (Note 1) 0.75 - 1.20 i Nicsel 0.06 -

l Molybder,um 0.19 0.15 - 0.25 l Vanadi um <0.0 5 -

Columbium + Tantalum <0.05 -

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l COP 9fENTS: 1) Chromium value exceeds specification requirements even factoring in pemissible variations (0.05% over). 2) Carbon content below minimum level after factoring permissible variation. Note: inadvertently not identified on original 10/30/87 report.

Enclosure I

METALLURGICAL EVALUATION BOLT IDENTIFICATION: S0-18 BOLT SPECIFICATION: A193-B7 BOLT SIZE: 3/4 - 10 UNC Methodolocy:

1. A section was cut from the bolt, mounted in epoxy, then metallurgically ground, polished and etched (2% Nital). The section showed (Figure 1) a tempered martensite microstructure consistent with this type of material.
2. Half of the fracture face (after tensile testing) was examined under the scanning election microscope (SEM) (Figure 2). The resulting fractograph showed a dimpled rupture appearance which indicated good ductility in the fracture.

Conclusions:

The bolt is considered to be suitable for service for the following reasons:

1. The polished section showed a microstructure consistent for this grade of bolt. The SEM examination revealed that the fracture (after tensile testing) was ductile in nature. This coupled with the fact that the bolt met the tensile requiremsnts of A193-B7 material and was only 0.01% below the minimum carbon level and 0.35% above the maximum chromium level (all other chemical requirements were met) leads one to believe that the ten-sile requirements will not be a problem for this bolt. The only other major consideration would be if the bolt could fail in a brittle (as opposed to ductile) manner in service (Notch Toughness) due to these chem-ical composition variances.

The Metals Handbook, 8th Edition, Vol. 1, Properties and Selection of Metals, defined Notch Toughness as:

".. .the ability of a metal to yield plastically under high localized stress, such as might occur at the root of a notch..."

This measure of a material's property would be very applicable to

! fasteners.

l l Carbon Content This same reference mentions that as carbon content is raised in the range l

from 0.15 to 0.80% in normalized plain carbon steels, the notch toughness decreases (at room temperature). This lowering of energy absorption is accompanied by a subsequent raising of the transition temperature (6*F per 0.01% increase in carbon content above 0.30% carbon). The net effect of this lower amount of carbon on this particular bolt would then be to increase the amount of energy absorbed and decrease the transition temper-ature as much as 6*F. Both of which should be beneficial to the bolt's "suitability for service."

2-80LT IDENTIFICATION: S0-18 BOLT SPECIFICATION: A193-B7

. BOLT SIZE: 3/4 - 10 UNC

_ Chromium Content

. The . Metals Handbook , 8th Edition, Vol. 1, Properties and Selection ~ of Metals, states:

Chromium has slight effect on transition temperature..."

-Since the impact properties should not be significantly impaired due to the higher chromium content, the bolt is considered "suitable for service."

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l BOLT IDENTIFICATION: S0-19 BOLT SPECIFICATION: A193-B7 BOLT SIZE: 1" - 8 UNC TENSILE STRENGTH:

Actual ' Required by Specification 143.03 ksi 125 ksi (min.)

Failure Location - Shoulder HARDNESS:

Actual Required by Specification 27.6 R Not Required CHEMICAL ANALYSIS:

Actual w/o Required by Specification w/o Carbon 0.40 0.37 - 0.49 Hanganese 0.98 0.65 - 1.10 Phosphorus 0.005 0.035 max Sulfur 0.016 0.040 max Silicon 0.21 0.15 - 0.35 Chromium 1.80 (Note 1) 0.75 - 1.20 Nickel 0.34 -

Molybdenum 0.19 0.15 - 0.25 Vanadium <0.05 -

Columbium + Tantalum <0.05 -

< = Less than COMMENTS: 1) Chromium value exceeds specification requirements even factoring in oermissible variations (0.05% over)

METALLURGICAL EVALUATION BOLT IDENTIFICATION: S0-19 BOLT SPECIFICATION: A193-87 BOLf SIZE: 1"- 8 UNC Methodology:

1. A section was cut from the bolt, mounted in epoxy, then metallurgically ground, polished and etched (2% Nital). The section showed (Figure 3) a tempered martensite microstructure consistent with this type of material.
2. Half of the. fracture face (after tensile testing) was examined under the scanning election microscope (SEM) (Figure 4). The resulting fractograph showed e dimpled rupture appearance which indicated good ductility in the fracture.

Conclusions:

The bolt is considered to be suitable for service for the following reasons:

1. The polished section showed a microstructure consistent for.this grade of bolt. The SEM examination revealed that the fracture (after tensile testing) was ductile in nature. These observations plus the fact that the bolt met the tensile requirements and all of the chemical requirements (except chromium) of the specification leads one to examine the ability of the bolt to resist rapid failure (notch toughness).

Chromium Content The Metals Handbook, 8th Edition, Vol. 1, Properties and Selection of Metals, states:

"Chromium has siight effect on transition temperature..."

Since the impact properties should not be significantly impaired due to the higher chromium content, the bolt is considered "suitable for service."

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Figure 3 Optical photomicrograph of tempered Figure 4 SEM fractograph of S0-19 showing martensite structure of S0-19 (400X). ductile failure (IC00X).

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BOLT IDENTIFICATION: S0-20 BOLT SPECIFICATION: A 193-B7

'80LT SIZE: 3/8" - 16 UNC TENSILE STRENGTH:

Actual Required by Specification 151.74 ksi 125 ksi (min.)

Failure Location - Threads HARDhESS:

Actual Required by Specification 23.83 R Not Required c

CHEMICAL ANALYSIS:

Actual w/o Required by Specification w/o Carbon 0.41 0.37 - 0.49 tianganese 0.97 0.65 - 1.10 Phosphorus <0.000 0.035 max Sulfur 0.008 0.040 max Silicon 0.27 0.15 - 0.35 Chromium -1.51 (Note 1) 0.75 - 1.20 Nickel 0.05 -

Molybdenum 0.22 0.15 - 0.25 Vanadi um <0.05 -

Columbium + Tantalum <0.05 -

< = Less than COMMENTS: 1) Chromium value exceeds specification requirements even factoring l

in pernissible variations (0.05% over)

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7 METALLURGICAL EVALUATION BOLT IDENTIFICATION: S0-20 BOLT SPECIFICATION: A193-B7 BOLT SIZE: 3/8" - 16 UNC Methodology:

1. A section was cut from the bolt, mounted in epoxy, then metallurgically ground, polished and etched (2% Nital). The section showed (Figure 5) a tempered martensite microstructure consistent with this type of material.
2. Half of the f racture face (after tensile testing) was examined under the scanning election microscope (SEM) (Figure 6). The resulting fractograph showed a dimpled rupture appearance which indicated good ductility in the fracture.

Conclusions:

The bolt is considered to be suitable for service for the following reasons:

1. The polished section showed a microstructure consistent for this grade of bolt. The SEM examination revealed that the fracture (after tensile testing) was ductile in nature. These observations plus the fact that the bolt met the tensile requirements and all of the chemical requirements (except chromium) of the specification leads one to examine the ability of the bolt to resist rapid failure (notch toughness).

Chromium Content The Metals Handbook, 8th Edition, Vol. 1, Properties and Selection of Metals, states:

"Chromium has slight effect on transition temperature..."

Since th~e impact properties should not be significantly impaired due to the higher chromium content, the bolt is considered "suitable for service."

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BOLT IDENTIFICATION: S0-21 BOLT SPECIFICATION: A193-B7 BOLT SIZE: 1/4" - 20 UNC TENSILE STRENGTH:

Actual ' Required by Specification 158.80 ksi 125 ksi (min.)

Failure Location - Threads HARDNESS:

Actual Required by Specification 62.6 R Not Required A

CHEMICAL ANALYSIS:

Actual w/o Required by Specification w/o Carbon 0.41 , 0.37 - 0.49 Manganese 0.94 0.65 - 1.10 Phosphorus 0.020 0.035 max Sulfur 0.024 0.040 max Silicon 0.27 0.15 - 0.35 Chromium 1.46 (Note 1) 0.75 - 1.20 Nickel 0.47 -

Molybdenum 0.23 0.15 - 0.25 Vanadi um <0.05 -

Columbium + Tantalum <0.05 -

< = Less than COMMENTS: 1) Chromium value exceeds specification reauirements even factorino in permissible variations (0.05% over)

METALLURGICAL EVALVATION BOLT IDENTIFICATION: S0-21 BOLT SPECIFICATION: A193-B7 BOLT SIZE: 1/4" - 20 UNC Methodology:

1. A section was cut from the bolt, mounted in epoxy, then metallurgically ground, polished and etched (2% Nital). The section showed (Figure 7) a tempered martensite microstructure consistent with this type of material.
2. Half of the fracture face (after tensile testing) was examined under the scanning election microscope (SEti) (Figure 8). The resulting fractograph showed a dimpled rupture appearance which indicated good ductility in the fracture.

Conclusions:

The bolt is considered to be suitable for service for the following reasons:

1. The polished section shewed a microstructure consistent for this grade of bolt. The SEM examination revealed that the fracture (after tensile testing) was ductile in nature. These observations plus the fact that the bolt met the tensile requirements and all of the chemical requirements (except chromium) of the specification leads one to examine the ability of the bolt to resist rapid failure (notch toughness).

Chromium Content The Metals Handbook, 8th Edition,, Vol. 1, Properties and Selection of Metals, states:

"Chromium has slight effect on transition temperature..."

Since the impact properties should not be significantly impaired dt.e to l the higher chromium content, the bolt is considered "suitable for service."

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F39ure 7 Optical photomicrograph of tenpered Figure 8 SEM fractograph of S0-21 showing martensite structure of S0-21 (400X). ductile failure (1000"'.

'4 BOLT IDENTIFICATION: 50-23 BOI.T SPECIFICATION: A 193-88 BOLT SIZE: 5/8" - 11 UNC TENSILE STRENGTH:

Actual Required by Specification 89.65 ksi 75 ksi (min.)

Failure Location - Threads HARDNESS:

Actual Required by Specification 63.6 RA (Note 1) 223 HB (max.)

(equates to 262 HB)

CHEMICAL ANALYSIS:

. A tual w/o Required by Specification w/o Carbon 0.06 0.08 max Manganese 1.75 2.00 max Phosphorus 0.050 (Note 2) 0.045 max Sulfur 0.021 0.030 max Silicon 0.72 1.00 max Chromium 19.0 18.00 - 20.00 Nickel 9.0 8.00 - 10.50 Molybdenum 0.40 -

Vanadi um <0.05 -

Columbium + Tantalum <0.05 -

< = Less than COMMENTS: 1) Although specification allows a maximum hardness of 241 HB 1A193),thisboltexceedshardnessmaximum. 2) Permissible variation for gh,o,sphorus (0.010% over) by specification allows accep,tance of this value.

,_ METALLURGICAL EVALUATION BOLT IDENTIFICATION: S0-23 BOLT SPECIFICATION: A193-B8 BOLT SIZE: 5/8" - 11 UNC Methodology:

1. A section was cut from the bolt, mounted in epoxy, then metallurgically ground, polished and etched (electrolytic oxalic acid). The section-showed (Figure 9) an austenitic microstructure consistent with this type of material.
2. Half cf the fracture face (after tensile testing) was examined under the SEM (Figure 10). The resultant fractograph showed a dimpled rupture appearance which_ indicates good ductility.
3. Consistent with the requirements of ASTH A370-77, a transverse section through the. bolt was cut and six hardness readings taken along the axial length.

Conclusions:

The bolt is considered to meet specification (ASTM A193-81a) requirements after hardness retesting. The specification requirements allow a maximum hardness of 223HB (with a maximum hardness of 241HD allowed for 3/4" diameter -

and smaller bolts), the six hardness retests showed the following hardnesses: >

RB 82, 83, 82, 85, 79, 88.5 Rg 89.5, equates to 181 HB All of which are below the specification maximum.

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i Figure 9 Optical phetomicrograph of austenitic Figure 16 SEM fractograph of S0-23 showing ,

structure seen on 50-23 (400X). ductile failure (450X).

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