EFFECTS OF WC ADDITION AND HOT PRESSING ON THE DIRECTIONAL MICROSTRUCTURE AND MECHANICAL PROPERTIES OF B4C-TiB2 COMPOSITES

Umut Savacı; Servet Turan

Article Details

EFFECTS OF WC ADDITION AND HOT PRESSING ON THE DIRECTIONAL MICROSTRUCTURE AND MECHANICAL PROPERTIES OF B4C-TiB2 COMPOSITES

Authors:

Umut Savacı | Servet Turan

Publisher:

Eskişehir Osmangazi University

Main Topics:

Malzeme Mühendisliği (Diğer)

Journal:

Eskişehir Osmangazi Üniversitesi Mühendislik ve Mimarlık Fakültesi Dergisi Vol.33 Issue 2, pp.1854-1864

Document Type:

Article

Publication Date:

8/2025

Document Language:

Turkish

Document ID (Org No.):

2001356301

pISSN:

2630-5712

Keywords:

Abstract:

 Boron carbide B4C is an important ceramic material used in applications such as cutting tools and armor due to its superior properties, including high hardness and low density. However, densification of pure B₄C through pressureless sintering is challenging, and this process is improved by adding dopants. Additionally, increasing electrical conductivity allows for easier shaping using machining methods such as EDM. Thus, the disadvantages of pure B4C are mitigated by producing ceramic composites with additive phases. To achieve high-density B4C ceramics, pressure-assisted sintering methods are preferred. Although these methods enable high density at lower temperatures, they can also cause crystallographic orientation in the microstructure depending on the direction of applied pressure. In this study, the effects of different milling methods and WC addition on the microstructure and mechanical properties of B4C - TiB2 ceramic composites produced via hot pressing were investigated based on the applied pressure direction during production. For this purpose, in addition to conventional microstructural characterization tools, advanced microscopy techniques were used for microstructural analyses. Furthermore, detailed analyses were conducted to examine the solid solution phases formed during hot pressing. The obtained results indicate that, depending on the powder preparation method and initial composition, crystallographic orientation varies between 6 and 10 in the microstructure after hot pressing, and Ti0.9W0.1B2 solid solution phases are formed. In addition to microstructural analyses, the direction-dependent mechanical properties of the obtained samples were examined, revealing that the degree of orientation did not lead to anisotropic behavior in mechanical properties.

 Boron carbide B4C is an important ceramic material used in applications such as cutting tools and armor due to its superior properties, including high hardness and low density. However, densification of pure B₄C through pressureless sintering is challenging, and this process is improved by adding dopants. Additionally, increasing electrical conductivity allows for easier shaping using machining methods such as EDM. Thus, the disadvantages of pure B4C are mitigated by producing ceramic composites with additive phases. To achieve high-density B4C ceramics, pressure-assisted sintering methods are preferred. Although these methods enable high density at lower temperatures, they can also cause crystallographic orientation in the microstructure depending on the direction of applied pressure. In this study, the effects of different milling methods and WC addition on the microstructure and mechanical properties of B4C - TiB2 ceramic composites produced via hot pressing were investigated based on the applied pressure direction during production. For this purpose, in addition to conventional microstructural characterization tools, advanced microscopy techniques were used for microstructural analyses. Furthermore, detailed analyses were conducted to examine the solid solution phases formed during hot pressing. The obtained results indicate that, depending on the powder preparation method and initial composition, crystallographic orientation varies between 6 and 10 in the microstructure after hot pressing, and Ti0.9W0.1B2 solid solution phases are formed. In addition to microstructural analyses, the direction-dependent mechanical properties of the obtained samples were examined, revealing that the degree of orientation did not lead to anisotropic behavior in mechanical properties.

 Boron carbide B4C is an important ceramic material used in applications such as cutting tools and armor due to its superior properties, including high hardness and low density. However, densification of pure B₄C through pressureless sintering is challenging, and this process is improved by adding dopants. Additionally, increasing electrical conductivity allows for easier shaping using machining methods such as EDM. Thus, the disadvantages of pure B4C are mitigated by producing ceramic composites with additive phases. To achieve high-density B4C ceramics, pressure-assisted sintering methods are preferred. Although these methods enable high density at lower temperatures, they can also cause crystallographic orientation in the microstructure depending on the direction of applied pressure. In this study, the effects of different milling methods and WC addition on the microstructure and mechanical properties of B4C - TiB2 ceramic composites produced via hot pressing were investigated based on the applied pressure direction during production. For this purpose, in addition to conventional microstructural characterization tools, advanced microscopy techniques were used for microstructural analyses. Furthermore, detailed analyses were conducted to examine the solid solution phases formed during hot pressing. The obtained results indicate that, depending on the powder preparation method and initial composition, crystallographic orientation varies between 6 and 10 in the microstructure after hot pressing, and Ti0.9W0.1B2 solid solution phases are formed. In addition to microstructural analyses, the direction-dependent mechanical properties of the obtained samples were examined, revealing that the degree of orientation did not lead to anisotropic behavior in mechanical properties.

 Bor karbür B4C, yüksek sertlik ve düşük yoğunluk gibi üstün özellikleri sayesinde kesici takımlar ve zırh gibi alanlarda kullanılan önemli bir seramik malzemedir. Ancak, basınçsız sinterleme ile saf B₄Cnin yoğunlaştırılması zor olup, ilave edilen katkı maddeleri ile bu süreç iyileştirilmektedir. Ayrıca, elektriksel iletkenliğin artırılmasıyla da tel erozyon gibi işleme yöntemleriyle daha kolay şekillendirilebilir hale getirilebilmesi mümkün olmaktadır. Böylelikle saf B4Cnin sahip olduğu dezavantajlar, katkı maddeleriyle elde edilen seramik kompozitlerin üretilmesiyle ortadan kaldırılmaya çalışılmaktadır. B₄C seramiklerinin yüksek yoğunlukta üretilmesi için ayrıca basınç destekli sinterleme yöntemleri tercih edilmektedir. Ancak bu yöntemler düşük sıcaklıklarda yüksek yoğunluk elde edilebilmesini mümkün kılsa da mikroyapıda basınç yönüne bağlı olarak kristalografik yönelime sebep olabilmektedir. Bu çalışmada farklı öğütme yöntemlerinin ve WC ilavesinin sıcak presleme yöntemiyle üretilmiş B4C-TiB2 seramik kompozitlerinin mikroyapısına ve mekanik özelliklerine olan etkileri üretim esnasında uygulanan basınç yönüne bağlı olarak araştırılmıştır. Bu amaçla geleneksel mikroyapı karakterizasyon araçlarının yanı sıra gelişmiş mikroskopi teknikleri de kullanılarak mikroyapısal incelemeler gerçekleştirilmiştir. Ayrıca yapılan detaylı analizler ile sıcak presleme sırasında oluşan katı çözelti fazları araştırılmıştır. Elde edilen sonuçlar, toz hazırlama yöntemine ve başlangıç kompozisyonuna bağlı olarak sıcak presleme sonrasında mikroyapıda  6 ila  10 arasında değişen oranlarda kristalografik yönlenme mevcut olduğunu ve Ti0,9W0,1B2 katı çözelti fazlarının meydana geldiğini göstermektedir. Mikroyapısal incelemelerin yanı sıra elde edilen örneklerin yöne bağlı mekanik özellikleri araştırılmış olup, meydana gelen yönlenme miktarının mekanik özelliklerde anizotropik bir davranışa yol açmadığı tespit edilmiştir.

Article Details

EFFECTS OF WC ADDITION AND HOT PRESSING ON THE DIRECTIONAL MICROSTRUCTURE AND MECHANICAL PROPERTIES OF B4C-TiB2 COMPOSITES

Authors:

Umut Savacı | Servet Turan

Publisher:

Eskişehir Osmangazi University

Main Topics:

Malzeme Mühendisliği (Diğer)

Journal:

Eskişehir Osmangazi Üniversitesi Mühendislik ve Mimarlık Fakültesi Dergisi Vol.33 Issue 2, pp.1854-1864

Document Type:

Article

Publication Date:

8/2025

Document Language:

Turkish

Document ID (Org No.):

2001356301

pISSN:

2630-5712

Electron Microscopy

Precession electron diffraction

Orientation imaging

Ceramic composite

Boron carbideElektron Mikroskopisi

Devinimli elektron kırınımı

Oryantasyon haritalama

Seramik kompozit

Bor karbür

Issues

Article Details

Authors: Umut Savacı | Servet Turan

Publisher: Eskişehir Osmangazi University

Main Topics: Malzeme Mühendisliği (Diğer)

Journal: Eskişehir Osmangazi Üniversitesi Mühendislik ve Mimarlık Fakültesi Dergisi Vol.33 Issue 2, pp.1854-1864

Document Type: Article

Publication Date: 8/2025

Document Language: Turkish

Document ID (Org No.): 2001356301

pISSN: 2630-5712

Issues

Authors:

Umut Savacı | Servet Turan

Publisher:

Eskişehir Osmangazi University

Main Topics:

Malzeme Mühendisliği (Diğer)

Journal:

Eskişehir Osmangazi Üniversitesi Mühendislik ve Mimarlık Fakültesi Dergisi Vol.33 Issue 2, pp.1854-1864

Document Type:

Article

Publication Date:

8/2025

Document Language:

Turkish

Document ID (Org No.):

2001356301

pISSN:

2630-5712