Black Sleeves Metallurgical Investigation

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The black Import Sleeves were tested to see how they compared to Domestic sleeves and Crosby sleeves. The following comparative analysis was based on three areas of criteria:

Transcript of Black Sleeves Metallurgical Investigation

  • Metallurgical Investigation Conducted for Baydar and Associates (B&A) of Black Import Flemish Eye

    Sleeves

    December 29, 2011

    Completed by:

    George Jarjoura, Ph.D., P.Eng. Momotaj Aghdasi, P.Eng.

    Faculty of Engineering Dalhousie University

    P.O. Box 1000 Halifax, Nova Scotia B3J 2X

  • 1

    Introduction Baydar & Associates Inc. (B&A), a company based in Halifax, Nova Scotia, has been in

    the rigging industry since 1999. Despite an impeccable safety record, the company has been

    having problems with some Flemish eye sleeves that cracked (failed) during swaging in the past.

    Previously, Dalhousie University had done a comparative product analysis between black (non-

    galvanized) B&A domestic Flemish eye sleeves and the black Crosby Flemish eye sleeve.

    Recently, Dr. George Jarjoura of the Materials Engineering Program at Dalhousie University has

    been approached to examine a new set of black Import sleeve samples to ensure quality of the

    batch and to see how they compare with the B&A domestic sleeves and the Crosby sleeves.

    One set of black Import Flemish eye sleeve samples were provided by Baydar &

    Associates Inc. as materials for examination. Three un-swaged black Import samples (sleeve sizes

    5/8, 1/2 and 3/8), one swaged black Crosby sample (sleeve size 5/8) and one swaged black

    Import (sleeve size 5/8) were provided for analysis.

    Comparative Product Analysis

    The black Import Sleeves were tested to see how they compared to Domestic sleeves and

    Crosby sleeves. The following comparative analysis was based on three areas of criteria:

    1. Alloy Composition

    2. Microstructure

    3. Material Hardness

    Alloy Composition

    A chemical analysis was conducted on the three black Import samples, the swaged black

    Import sample and the swaged black Crosby sample and the results were compared to standard

    composition of Steel 1010 as defined by ASI-SAE, B&A Domestic sleeves and Crosby sleeves.

    The results are presented below in Table 1. Data used in Table 1 for Crosby and B&A Domestic

    sleeves were taken from previous reports[1],[2]. Due to equipment issues at the laboratory, the

    amount of carbon in one of the black Import samples was unable to be determined. The

    compositional results in Table 1 has shown that both the B&A Domestic and the Crosby samples

    fall within standard specifications for 1010 Steel, however the black Import samples do not.

  • 2

    Table 1: Comparative analysis of alloy composition

    Element wt% Fe C P S Cu Mn Al Cr Si ASI-ASE Steel

    1010 Balance 0.08-

    0.13 0.040 0.050 0.20 0.30-

    0.60 0.1 Max

    Black Crosby Balance 0.128 0.002 0.022 0.027 0.414 0.045 0.028 0.066 Black B&A Domestic

    Balance 0.094 0.007 0.007 0.045 0.383 0.038 0.044 0.099

    Black Import 1 (Size 5/8")

    Balance 0.029 0.012 0.015 0.024 0.084 0.044 0.013 0.013

    Black Import 2 (Size 1/2")

    Balance N/A 0.012 0.018 0.018 0.108 0.033 0.016 0.022

    Black Import 3 (Size 3/8")

    Balance 0.030

    0.014 0.018 0.016 0.087 0.052 0.053 0.014

    Swaged Black Crosby

    (Size 5/8")

    Balance 0.098

    0.013 0.001 0.042 0.363 0.041 0.092 0.115

    Swaged Black Import

    (Size 5/8")

    Balance 0.024

    0.011 0.004 0.026 0.074 0.025 0.022 0.033

    The black Import sleeves were then compared with several other low-carbon steels[3] and

    the results are presented in Table 2. The compositional results in Table 2 have shown that the

    black Import samples fall close to within standard specification for 1005 steel rather than 1010

    steel. Although the amount of carbon is undetermined in one of the black Import sleeve (size

    1/2"), based on the weight percent (wt%) of some other elements present in that sample, it has

    similar composition as the other two un-swaged black Import samples and the swaged black

    Import sample.

    Table 2: Comparative analysis of alloy composition between black Import sample and few low-carbon steels.

    Element wt% C Mn P S ASI-ASE Steel

    1005 0.06 max 0.35 max 0.040 0.050

    ASI-ASE Steel 1006

    0.08 max 0.25-0.40 0.040 0.050

    ASI-ASE Steel 1008

    0.10 max 0.30-0.50 0.040 0.050

    Black Import 1 (Size 5/8")

    0.029 0.084 0.012 0.015

    Black Import 2 (Size 1/2")

    N/A 0.108 0.012 0.018

    Black Import 3 (Size 3/8")

    0.030

    0.087 0.014 0.018

    Swaged Black Import

    (Size 5/8")

    0.024

    0.074 0.011 0.004

  • 3

    Microstructure

    The three black Import samples, the swaged black Crosby sample and the swaged black

    Import sample were cross sectioned, ground, polished and etched using Nital acid solution. The

    microstructures of these samples were viewed under an optical microscope at different

    magnifications. The micrographs in Figure 1 compared the microstructures of an un-swaged

    black Import sample with a swaged black Import sample and a swaged black Crosby sample. The

    micrographs showing the microstructure of the other two un-swaged black Import samples are

    presented in Appendix A. The micrographs in Figure 1 and Appendix A have shown that all

    three black Import samples have a spheroidite structure as well as uniform and equiaxed grains,

    which allows for a high degree of deformability and swaging. Both swaged samples do show

    smaller and elongated uniform grains, which is a result of cold working operation as expected.

    The difference in grain structure for the swaged black Crosby sample and swaged black Import

    sample would suggest that the heat treatments between the black Import and the Crosby are

    somewhat different and indicate presence of different amount of alloying elements as seen in

    Table 1. Also, the micrographs in Figure 1(e) and Figure 1(f) indicated the swaged Crosby

    sample reacted differently to the etchant in comparison to the black Import samples.

  • 4

    (a) Un-swaged Black Import Sample (Size 5/8")

    Image#1 (b) Un-swaged Black Import Sample (Size 5/8")

    Image#2

    (c) Swaged Black Import Sample (Size 5/8")

    Image#1 (d) Swaged Black Import Sample (Size 5/8")

    Image#2

    (e) Swaged Black Crosby Sample (Size 5/8")

    Image#1 (f) Swaged Black Crosby Sample (Size 5/8")

    Image#2 Figure 1: Micrographs at different magnifications showing microstructures of an un-swaged black Import

    sleeve sample, a swaged black Import sleeve sample and a swaged black Crosby sleeve sample.

  • 5

    Material Hardness

    Several hardness measurements were taken from each of the sectioned samples. The

    average hardness values calculated for the three un-swaged black Import samples, the swaged

    black Import sample and the swaged black Crosby sample are shown in Table 3 and compared to

    standard annealed 1010 Steel, un-swaged black Crosby sample, un-swaged black B&A Domestic

    and swaged black B&A Domestic samples. Data used in Table 3 for un-swaged Crosby, un-

    swaged B&A Domestic and swaged B&A Domestic samples were taken from previous

    reports[1],[2].

    Table 3: Comparative Hardness testing measurements

    Sample Hardness (HRB)

    Black Import Sleeve 1 (Size 5/8") 35.7 Black Import Sleeve 2 (Size 1/2") 36.6 Black Import Sleeve 3 (Size 3/8") 34.2

    Black Crosby Sleeve 44.1 Black B&A Domestic Sleeve 50.8-51.6

    ASI-ASE Steel 1010, Spheroidized 40-55 Swaged Black Domestic Sample 83.8

    Swaged Black Crosby Sample (Sleeve Size 5/8) 79.6 Swaged Black Import Sample (Sleeve Size 5/8) 77.9

    From the results of the hardness measurements in Table 3, it is clear that both B&A

    Domestic and Crosby samples fall well within the limits for the spheroidized AISI 1010 steel.

    However, the overall average hardness of all three un-swaged black Import samples were lower

    and is outside the limits of the spheroidized 1010 steel. As per Table 3, the increased hardness

    values of all three swaged samples were a result of work hardening of the sleeves during the

    swaging process. The average hardness value of the swaged black Import sample was very close

    to the average hardness of the swaged Crosby sample.

  • 6

    Conclusion From the results and information gathered it appears that the black Import sleeves are not

    made from the same steel type as the Crosby and B&A Domestic Sleeves. However, all the black

    Import sleeve samples contained a host alloying elements of some amount, which improve their

    resistance to atmospheric corrosion and further enhance their machinability, forgeability and

    swageability.

    The microstructures of the black Import sleeve samples showed a spheroidite structure as

    well as uniform and equiaxed grains, which allows for a high degree of deformability and

    swaging.

    The lower hardness values of the black Import sleeve samples would indicate that the

    black Import sleeves are more ductile than both the Crosby and the B&A Domestic sleeves. The

    difference in hardness between the swaged black Import sample and both swaged B&A Domestic

    and Crosby samples was small in comparison to the difference prior to the swaging process.

    Both the swaged black Import samples and the swaged black Crosby sample did not show

    any cracks on the surface or the interface between the wire bundle and the swaged sleeve under

    visual inspection following the swaging operation. Under t